JP4062292B2 - Light alloy casting manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a light alloy casting in which a light alloy casting such as an aluminum alloy or a magnesium alloy is cast using a mold.

Generally, an aluminum alloy casting or a magnesium alloy casting is subjected to heat treatment for the purpose of improving mechanical properties such as strength.
As the above heat treatment, T6 treatment (heat treatment for artificial age hardening after solution treatment) is effective. In the case of an aluminum alloy casting, T6 treatment is performed, for example, at a temperature of about 500 ° C. for 8 to 10 hours. After that, an artificial aging treatment is performed at around 180 ° C. for 5 to 10 hours, and this artificial aging treatment is performed by placing an aluminum alloy casting in a heating furnace (aging furnace). In addition to the necessity of a heating furnace, there is a problem that energy consumption becomes large.

On the other hand, as a method for casting an aluminum alloy casting using a mold, there are the following methods.
That is, when the cylinder block of the V-type engine is cast with an aluminum alloy casting, the part corresponding to the combustion chamber side of the cylinder block is constituted by a mold, and the other part is constituted by a sand mold, and these molds and sand molds are used. A runner is attached to the formed cavity and feeder part via a sealing mechanism, and molten aluminum alloy is poured from below into the cavity via the runner, open sealing mechanism and feeder part, and then After closing the sealing mechanism, the entire mold consisting of a mold and a sand mold is reversed, and after the molten metal solidifies, the mold is first separated, and the casting surface of the separated portion is cooled with a liquid cooling medium, and oriented. (See Patent Document 1).

  However, in this conventional method disclosed in Patent Document 1, since it is necessary to invert the entire mold, there is a problem that the casting apparatus becomes complicated, and solution treatment (quenching) and aging treatment are performed after casting. Since there is no description or suggestion about the application point, there is a problem that sufficient mechanical properties such as strength of an aluminum alloy casting cannot be obtained.

  As another conventional method, a molten aluminum alloy is pressurized and filled in a mold at a casting pressure of 49 MPa or more and solidified, and after the solidification is completed, the casting is taken out of the mold and immediately immersed in water for quenching. There is one that performs artificial aging treatment after application and quenching (see Patent Document 2).

The conventional method disclosed in Patent Document 2 is a method of casting using a mold, and the above heat treatment (quenching, artificial aging treatment) is a process after taking a product (casting) out of the mold. For some reasons, artificial aging treatments inevitably require an aging furnace, which is considered to increase energy consumption.
Japanese Patent No. 3068185 JP-A-8-225903

  Therefore, the present invention forms a cavity with a sand mold having a feeder part and a mold, separates only the mold after casting, and locally cools the surface of the casting from which the mold is separated by a cooling medium. The product is subjected to T6 treatment without requiring any heat treatment furnace (aging furnace) by effectively using the heat retained in the hot-water supply section and performing aging treatment by quenching (solution treatment). An object of the present invention is to provide a light alloy casting manufacturing method capable of sufficiently improving mechanical properties such as strength.

  The light alloy casting manufacturing method according to the present invention provides a preparation for preparing a mold that constitutes a cavity with a sand mold that forms a feeder part and a mold that is arranged apart from the feeder part and forms a part of the cavity. A casting step of casting a light alloy molten metal into the cavity, a separation step of separating the mold after casting, and quenching by quenching the casting by bringing a cooling medium into contact with the surface of the casting from which the mold has been separated. And a aging treatment step of covering the casting with the sand mold and the heat retaining means and keeping the entire casting at the aging treatment temperature for a predetermined time by the heat retained in the hot water feeder.

  As the light alloy, an aluminum alloy such as JIS standard AC4B or a magnesium alloy such as JIS standard MC1 can be used. Further, water can be used as the cooling medium, and the manufactured casting may be set in the cylinder head of the engine.

  According to the above configuration, in the preparation process, a mold having a cavity is configured by both the sand mold and the mold, in the casting process, the light alloy molten metal is cast into the cavity, and in the next separation process, after casting. Only the mold is separated (released) with the sand mold left, and in the next quenching process, the cooling medium is brought into contact with the surface of the cast from which the mold has been separated, and the casting is quenched, and the next aging treatment is performed. In the process, the casting is covered with the above-mentioned sand mold and heat retaining means, and the entire casting is kept at the aging treatment temperature for a predetermined time with the retained heat of the hot water feeder.

  Thus, after the mold separation, the necessary part is quenched by the local cooling with the cooling medium, and the retained heat of the hot-water supply part is effectively used to perform quenching (solution treatment) and aging treatment easily. In addition, the aging treatment is carried out by covering the casting with a sand mold and heat retaining means and effectively using the heat retained in the hot water feeder section, so that no heat treatment furnace (aging furnace) is required and energy consumption is also required. However, the T6 treatment can be applied to sufficiently improve the mechanical properties such as the strength of the product.

  The light alloy casting manufacturing method according to the present invention also prepares a mold that forms a cavity with a sand mold that forms a feeder part and a mold that is arranged away from the feeder part and forms a part of the cavity. A casting step of casting a light alloy molten metal into the cavity, a separation step of separating the mold after casting, and quenching the casting by spraying a cooling medium on the surface of the casting from which the mold has been separated. A quenching process, a continuation process in which the spraying state of the cooling medium is continued for a predetermined time, and then the spraying is stopped. The casting is covered with the sand mold and the heat retaining means, and the entire casting is aged with the retained heat of the hot water portion. And an aging treatment step of maintaining the treatment temperature for a predetermined time.

  According to the above configuration, in the preparation process, a mold having a cavity is configured by both the sand mold and the mold, in the casting process, the light alloy molten metal is cast into the cavity, and in the next separation process, after casting. Only the mold is separated (released) while leaving the sand mold, and in the next quenching process, the cooling medium is sprayed onto the surface of the casting from which the mold has been separated, and the casting is quenched, and in the next continuation process After the cooling medium spraying state has been continued for a predetermined time, the spraying is stopped, and in the next aging treatment process, the casting is covered with the above-mentioned sand mold and heat retaining means, and the entire casting is aged with the retained heat of the hot water feeder. Maintain the processing temperature for a predetermined time.

  Thus, after the mold separation, the necessary part is quenched by the local cooling with the cooling medium, and the retained heat of the hot-water supply part is effectively used to perform quenching (solution treatment) and aging treatment easily. In addition, the aging treatment is performed by covering the casting with the sand mold and the heat retaining means and effectively using the heat retained in the hot water portion, so that no heat treatment furnace (aging furnace) is required and energy consumption is also required. However, the T6 treatment can be applied to sufficiently improve the mechanical properties such as the strength of the product.

  The light alloy casting manufacturing method according to the present invention further provides a mold that forms a cavity with a sand mold that forms a feeder part and a mold that is arranged away from the feeder part and forms a part of the cavity. A casting process in which a molten light alloy is cast into the cavity, a separating process in which the mold is separated after casting, and a quenching cooling medium is sprayed onto the surface of the casting from which the mold has been separated. A quenching process for quenching, a cooling medium for adjusting cooling is sprayed on the surface of the casting after quenching and cooling is continued for a predetermined time, and then the spraying is stopped, and the casting is covered with the sand mold and the heat retaining means. And an aging treatment step of keeping the entire casting at the aging treatment temperature for a predetermined time by the heat retained by the hot water feeder.

  Both the quenching cooling medium and the adjustment cooling cooling medium sprayed on the surface of the casting described above are set to water, spraying the cooling water in the quenching process, and spraying mist water (so-called fog water) in the continuing process. You may comprise so that it may spray. In addition, it is desirable to control the product temperature within a temperature range that can effectively bring out an aging phenomenon by switching from spraying cooling water to spraying fog water.

  According to the above configuration, in the preparation process, a mold having a cavity is configured by both the sand mold and the mold, in the casting process, the light alloy molten metal is cast into the cavity, and in the next separation process, after casting. Only the mold is separated (released) while leaving the sand mold, and in the next quenching process, a quenching cooling medium is sprayed onto the surface of the cast from which the mold has been separated, and the casting is quenched. In the continuation process, after quenching, the cooling medium for adjusting cooling is sprayed on the surface of the casting and the cooling is continued for a predetermined time. Then, the spraying is stopped, and in the next aging treatment process, the casting is washed with the sand mold and the heat retaining means. Covering and keeping the entire casting at the aging treatment temperature for a predetermined time by the heat retained by the hot water feeder.

  In this way, quenching (solution treatment) and aging treatment can be easily achieved by quenching the necessary part by local cooling with a cooling medium after mold separation and effectively utilizing the retained heat of the hot-water supply part. In addition, the aging treatment is performed by covering the casting with a sand mold and heat retaining means and effectively using the heat stored in the feeder, so there is no need for any heat treatment furnace (aging furnace) and energy consumption. In addition, the T6 treatment can be applied to sufficiently improve the mechanical properties such as the strength of the product.

Moreover, since the cooling medium for adjusting cooling is sprayed in the continuous process,
This cooling medium can be set to fog water or cooling air, and the fog water sprayed on the surface of the casting is vaporized. As a result, a fixed cooling station is not required, and the casting as the product can be adjusted and cooled during the conveyance of the product, so that the production efficiency can be improved.

  The method for producing a light alloy casting according to the present invention further includes a sand mold containing a water-soluble binder and having a feeder part formed therein, and a mold that is arranged away from the feeder part and forms a part of the cavity. A preparation step for preparing a mold constituting the cavity, a casting step for casting a light alloy molten metal into the cavity, a separation step for separating the mold after casting, and a cooling medium on the surface of the casting from which the mold has been separated. Spraying and quenching the casting, immersing the sand mold and casting in water to cool the casting, submerging the sand mold to submerge, and removing the casting from the water, and then covering the casting with heat retaining means And an aging treatment step of keeping the entire casting at the aging treatment temperature for a predetermined time by the heat retained by the hot water feeder.

The water-soluble binder described above is set to at least one inorganic sulfate compound of magnesium sulfate hydrate, aluminum sulfate hydrate, sodium sulfate hydrate, nickel sulfate hydrate, and manganese sulfate hydrate. In particular, magnesium sulfate hydrate is preferable for ensuring stable mold strength. On the other hand, the heat retaining means may be set to a heat insulating material.
According to the above configuration, in the preparation process, a mold having a cavity is configured by both the sand mold and the mold, in the casting process, the light alloy molten metal is cast into the cavity, and in the next separation process, after casting. Only the mold is separated (released) while leaving the sand mold, and in the next quenching process, the cooling medium is sprayed onto the surface of the casting from which the mold has been separated, the casting is quenched, and the next submerged process. In addition, the sand mold and casting are immersed in water to cool the casting, and the sand mold formed with the water-soluble binder is collapsed. The entire casting is kept at the aging treatment temperature for a predetermined time by the retained heat of the hot water feeder.

  In this way, quenching (solution treatment) and aging treatment can be easily achieved by quenching the necessary part by local cooling with a cooling medium after mold separation and effectively utilizing the retained heat of the hot-water supply part. In addition, the aging treatment is performed by covering the casting with the heat retaining means and effectively using the heat retained in the hot metal part, so that no heat treatment furnace (aging furnace) is required and no energy is consumed. By performing the treatment, the mechanical properties such as the strength of the product can be sufficiently improved.

  Moreover, since the sand mold and the casting are immersed in the water in the submerging process, the sand mold formed with the water-soluble binder can be separated and separated, and the excess temperature of the hot water can be lowered by submerging, so that the quenching process The cooling time of the casting from the subsequent aging treatment step can be efficiently shortened.

  The method for producing a light alloy casting according to the present invention further includes a sand mold containing a water-insoluble curable binder and formed with a feeder part, and is disposed apart from the feeder part to form a part of the cavity. A preparation process for preparing a mold that forms a cavity with a mold, a casting process for casting a molten light alloy into the cavity, a separation process for separating the mold after casting, and the sand mold and casting are immersed in water. A quenching process that cools the surface of the casting from which the mold has been separated, and after taking out the sand mold and casting from the water, the casting is covered with the sand mold and heat retaining means, and the entire casting is aged with the heat retained by the hot water feeder And an aging treatment step for maintaining the temperature for a predetermined time.

The water-insoluble curable binder described above contains a phenolic resin as a main material and a polyisocyanate as a curing agent, and is cured with an amine gas, or contains a phenolic resin as a main material and a hexamethylenetetramine as a curing agent. It may be set to be cured.
According to the above configuration, in the preparation process, a mold having a cavity is configured by both the sand mold and the mold, in the casting process, the light alloy molten metal is cast into the cavity, and in the next separation process, after casting. Only the mold is separated (released) while leaving the sand mold, and in the next quenching process, the sand mold and the casting are immersed in water to cool the surface of the casting from which the mold has been separated, and the casting is quenched. In the next aging treatment step, after the sand mold and the casting are taken out from the water, the casting is covered with the sand mold and the heat retaining means, and the entire casting is kept at the aging treatment temperature for a predetermined time by the retained heat of the hot water feeder.

  As described above, after separating the mold, the sand mold and the casting are immersed in water to cool the surface of the casting from which the mold has been separated, and necessary parts are quenched, and then the casting is covered with the sand mold and the heat retaining means. The aging treatment can be achieved by effectively using the heat retained in the hot water underneath, and the above-mentioned aging treatment is performed by covering the casting with heat retaining means and effectively utilizing the heat retained in the hot water portion. Therefore, the T6 treatment can be performed without requiring any heat treatment furnace (aging furnace) and without energy consumption, and the mechanical properties such as the strength of the product can be sufficiently improved.

  Moreover, since the sand mold and casting are immersed in water and quenching is performed, the excess temperature of the feeder can be lowered with water, resulting in efficient cooling of the casting from the quenching process to the aging treatment process. Can be shortened.

In one embodiment of the invention, the heat retaining means is set as a heat insulating material.
According to the said structure, heat insulating materials, such as a glass wool molded object and a gypsum board, are used as a heat retention means. That is, a low-temperature heater may be used as the heat retaining means, but if a heat insulating material is used without using a low-temperature heater, power consumption becomes unnecessary and energy saving can be achieved.

In one embodiment of the present invention, the light alloy casting is set to an aluminum alloy casting, the quenching temperature is set to 480 to 530 ° C, and the aging treatment is performed within a temperature range of 160 to 240 ° C. It was set to keep for 2 hours.
If the quenching temperature is 480 ° C. or lower, the solution treatment is insufficient, and if it is 530 ° C. or higher, the casting is softened and it is difficult to maintain the shape. Moreover, if the temperature of an aging treatment is 160 degrees C or less, it will take time for an aging treatment, and if it exceeds 240 degreeC, it will become overaging and intensity | strength will fall. Furthermore, the aging treatment time is required to be at least 1 hour, and a sufficient aging treatment effect can be obtained by keeping it for 2 hours.

According to the said structure, since heat processing conditions were set as mentioned above, sufficient tensile strength and proof stress of the manufactured casting can be ensured.
In one embodiment of the present invention, the light alloy casting is set to an aluminum alloy or magnesium alloy cylinder head, and the surface of the casting formed by the mold is set to the combustion chamber side of the cylinder head. It is.

  The above configuration has the following effects. That is, the molten metal on the combustion chamber side of the cylinder head in contact with the mold solidifies faster than the sand mold portion, the metal structure becomes dense, the dimensional accuracy of the casting is increased, and the combustion chamber side of the cylinder head is Heating and cooling are repeated during the operation of the engine. However, since the metal structure is fine and the T6 treatment is performed to improve the mechanical characteristics, it is also resistant to thermal fatigue cracks.

  According to the present invention, a cavity is constituted by a sand mold having a feeder part and a mold, only the mold is separated after casting, and the surface of the casting from which the mold is separated is locally cooled by the cooling medium. Then, the casting is quenched (solution treatment), and then the aging treatment is performed by effectively utilizing the heat retained in the hot metal part, so that the T6 treatment is performed without requiring any heat treatment furnace (aging furnace), There is an effect that the mechanical properties such as the strength of the product can be sufficiently improved.

  Without requiring any heat treatment furnace (aging furnace), the purpose of T6 treatment to sufficiently improve the mechanical properties such as strength of the product, sand mold with hot water part and mold After the casting, only the mold is separated, the surface of the casting from which the mold is separated is locally cooled with a cooling medium, and the casting is quenched (solution treatment). This was realized by a method of covering with a sand mold and performing an aging treatment by effectively using the heat retained in the hot water feeder.

An embodiment of the present invention will be described below in detail with reference to the drawings.
The drawing shows a light alloy casting manufacturing method. First, the structure of a mold used in this manufacturing method will be described with reference to FIG.

  This mold is composed of a plurality of sand molds 1 to 5, a core 6, and a mold 7. A hot metal part 8 (riser) is formed by sand molds 1, 2 and 3 among the plurality of sand molds 1 to 5, and a light alloy molten metal is formed at the end of the hot water part 8 in the cylinder head cylinder row direction (longitudinal direction). A pouring gate 9 (gate) for injecting molten aluminum alloy or molten magnesium alloy is formed.

  The sand molds 3, 4, 5 among the plurality of sand molds 1 to 5 and the metal mold 7 that is arranged apart from the hot water supply portion 8 and forms a part of the cavity constitute a cavity 10. In the cavity 10, the above-described core 6 made of a sand mold is disposed, and a plurality of runners 11 formed in the sand mold 3 (runner, but in the drawing, only one runner is shown for convenience of illustration). Thus, the upper feeder 8 and the lower cavity 10 are connected in communication.

  Since the casting cast in this embodiment is a cylinder head of an engine made of aluminum alloy or magnesium alloy, the surface of the casting formed by the mold 7 is set on the combustion chamber side of the cylinder head.

  When the cylinder head is made of an aluminum alloy, an aluminum alloy represented by JIS standard AC4B is used. In this aluminum alloy, Cu is 2.0 to 4.0%, Si is 7.0 to 10.0%, Mg is 0.6% or less, Zn is 1.0% or less, and Fe is 1.2% or less. , Mn is 0.8% or less, Ni is 0.5% or less, Ti is 0.2% or less, and the balance is aluminum.

On the other hand, when the cylinder head is made of a magnesium alloy, a magnesium alloy represented by JIS standard MC1 is used. This magnesium alloy has 5.3 to 6.7% Al and 2.5 to 3.5% Zn. It is an alloy corresponding to one type of magnesium alloy casting in which Mn is 0.15% to 0.6%, Si is 0.30 or less, Cu is 0.10% or less, Ni is 0.01% or less, and the balance is magnesium. .
Furthermore, the above-mentioned sand molds 1 to 5 and the core 6 are formed in advance using magnesium sulfate hydrate as a water-soluble binder and foundry sand.

Example 1
Next, a method for producing a light alloy casting using the above-described mold (see FIG. 1) will be described in detail with reference to FIGS.
In the following examples, a method of casting a cylinder head made of an aluminum alloy will be exemplified.
In the preparation step S1 of the process chart shown in FIG. 2, the cubity 10 is configured by the sand mold that forms the feeder section 8 and the mold 7 that is disposed apart from the feeder section 8 and forms part of the cavity 10. A mold (see FIG. 1) is prepared.

  Next, in the casting step S2 of the process diagram shown in FIG. 2, as shown in FIG. 3, the molten metal 12 of the aluminum alloy (JIS standard AC4B) is transferred from the gate 9 to the cavity 10 through the feeder 8 and the runner 11. When pouring, after the molten aluminum alloy 12 is solidified, as shown in FIG. 4, a cylinder head part 13 and a feeder part 14 are formed as castings.

Next, in the separation step S3 of the process chart shown in FIG. 2, only the mold 7 is separated with the sand molds 1 to 5 and the core 6 left after casting as shown in FIG.
Next, in the quenching step S4 of the process chart shown in FIG. 2, as a cooling medium on the surface of the cylinder head portion 13 as a casting from which the mold 7 is separated as shown in FIG. The required part of the casting is locally cooled and quenched.

  Here, the quenching temperature is set to 480 to 530 ° C., and water 15 from a plurality of nozzles 16 is sprayed onto the surface corresponding to the combustion chamber of the cylinder head portion 13 that is exposed to the mold surface after the mold 7 is separated. Then, the cylinder head portion 13 is subjected to solution treatment by rapid cooling to 300 ° C. or less in about 1 minute.

  In addition, since the water 15 sprayed from the nozzle 16 to the cylinder head part 13 flows down, the tank 17 which receives this water 15 is provided in cooling station ST1.

  Next, in the continuation step S5 of the process diagram shown in FIG. 2, the spraying state of the water 15 as the cooling medium is continued for a predetermined time in the same cooling station ST1 as in FIG. 6, and then the spraying is stopped.

  The timing of stopping the spraying of the water 15 is determined in the next aging treatment by the combustion chamber side A (hereinafter simply referred to as product part A) of the cylinder head 13 and the side B (hereinafter simply referred to as product) of the hot water supply part 14. The temperature is abbreviated as “Part B”) and is set to a timing at which reheating can be performed at 160 to 240 ° C. as an aging condition in consideration of heat transfer from the hot-water supply portion 14.

  In this embodiment, as shown in FIG. 8 showing the temperature transition of the casting, the water 15 spraying (showering) time in the quenching step S4 and the continuation step S5 is set to about 20 minutes in total, and the temperature of the product part A is set. a is lowered to 100 ° C. or lower, the temperature b of the product part B is lowered to 150 ° C. or lower, and the temperature c of the feeder 14 is lowered to around 300 ° C.

  Next, in the aging treatment step S6 of the process diagram shown in FIG. 2, the cylinder head part 13 and the hot water feeder part 14 as castings as shown in FIG. The formed body is covered with 18, and the entire casting is kept at the aging treatment temperature for a predetermined time by the heat retained by the hot water feeder section 14, and the aging treatment is performed.

This aging treatment is set so as to be maintained within a temperature range of 160 to 240 ° C. for 1 to 2 hours.
As shown in FIG. 7, when the cylinder head part 13, the hot water supply part 14, and the sand molds 1 to 5 are placed on the heat insulating material 18 with the sand molds 1 to 5 left on the outer periphery of the casting, the temperature of the casting is externally changed. The product parts A and B can receive heat conduction from the hot-water supply part 14 and can be reheated to a temperature range effective for aging. An aging treatment is performed. In particular, the product part A is subjected to the T6 treatment by both the quenching in the quenching step S4 and the aging treatment in the aging treatment step S6.

  9, 10, and 11 show measurement results of tensile strength, 0.2% proof stress, and elongation at break of product parts A and B according to the manufacturing method of the present embodiment as characteristic Z, and up to casting as a comparative example. The results of measuring the tensile strength, 0.2% proof stress, and elongation at break of the parts corresponding to the product parts A and B are shown as characteristics X for the samples left after being run (so-called as-cast). Results of measuring the tensile strength, 0.2% proof stress, and elongation at break of the parts corresponding to the product parts A and B in the case of performing cooling by showering after casting and releasing and performing no aging treatment. Is represented by characteristic y.

  As is apparent from FIGS. 9 and 10, the characteristic z by the manufacturing method of this example was superior to the characteristics x and y of the comparative example in both tensile strength and 0.2% proof stress.

  Further, as apparent from FIG. 11, the characteristic z by the manufacturing method of the present embodiment is sufficiently reduced in the elongation at break with respect to the characteristics x and y of the comparative example, but can satisfy the requirements as a product, that is, a cylinder head. .

  As described above, the light alloy casting manufacturing method according to the embodiment shown in FIGS. 1 to 11 is disposed apart from the sand molds 1 to 5 forming the feeder part 8 and the feeder part 8. A preparation step S1 for preparing a mold constituting the cavity 10 with a mold 7 that forms a part, a casting step S2 for casting a light alloy molten metal 12 into the cavity 10, and a separation for separating the die 7 after casting Step S3, a quenching step S4 for quenching the casting by bringing a cooling medium (see water 15) into contact with the surface of the casting from which the mold 7 has been separated, and covering the casting with the sand molds 1 to 5 and the heat insulating material 18 And an aging treatment step S6 for keeping the entire casting at the aging treatment temperature for a predetermined time by the heat retained by the hot-water supply portion 14.

  According to this configuration, in the preparation step S1, a mold including the cavity 10 is configured by both the sand molds 1 to 5 and the mold 7, and in the casting step S2, the light alloy molten metal 12 is cast into the cavity 10, In the next separation step S3, only the mold 7 is separated (mold release) while leaving the sand molds 1 to 5 after casting, and in the next quenching step S4, the surface of the casting from which the mold 7 has been separated is cooled. The medium is brought into contact, the casting is quenched, and in the next aging treatment step S6, the casting is covered with the above-described sand molds 1 to 5 and the heat insulating material 18, and the entire casting is subjected to the aging treatment temperature with the retained heat of the hot water feeder section 14. Keep for a predetermined time.

  As described above, after the mold 7 is separated, the necessary part is quenched by the local cooling with the cooling medium, and the retained heat of the hot-water supply part 14 is effectively used to easily perform quenching (solution treatment) and aging treatment. In addition, the aging treatment can be performed by covering the casting with the sand molds 1 to 5 and the heat insulating material 18 as a heat retaining means, and effectively using the retained heat of the feeder 14, so a heat treatment furnace (aging furnace) The T6 treatment can be performed without any energy consumption and without energy consumption, and the mechanical properties such as the strength of the product can be sufficiently improved.

  The light alloy casting manufacturing method of the embodiment shown in FIG. 1 to FIG. 11 is also arranged such that the sand molds 1 to 5 forming the feeder part 8 and the feeder part 8 are arranged apart from each other, and a part of the cavity 10. A preparation step S1 for preparing a mold constituting the cavity 10 with the mold 7 for forming a mold, a casting step S2 for casting the molten light alloy 12 into the cavity 10, and a separation step S3 for separating the die 7 after casting Then, a cooling medium (see water 15) is sprayed on the surface of the casting from which the mold 7 is separated, and the quenching step S4 for quenching the casting and the spraying state of the cooling medium (see water 15) are continued for a predetermined time. After that, the continuation step S5 for stopping the spraying, the casting is covered with the sand molds 1 to 5 and the heat retaining means (see the heat insulating material 18), and the entire casting is kept at the aging treatment temperature for a predetermined time with the retained heat of the hot-water supply part 14. Aging treatment step S6 to keep .

  According to this configuration, in the preparation step S1, a mold including the cavity 10 is configured by both the sand molds 1 to 5 and the mold 7, and in the casting step S2, the light alloy molten metal 12 is cast into the cavity 10, In the next separation step S3, only the mold 7 is separated (mold release) while leaving the sand molds 1 to 5 after casting, and in the next quenching step S4, the surface of the casting from which the mold 7 has been separated is cooled. Spraying the medium (see water 15), quenching the casting, in the next continuation step S5, after continuing the spraying state of the cooling medium for a predetermined time, stop the spraying, in the next aging treatment step S6, The casting is covered with the above-described sand molds 1 to 5 and the heat retaining means (see the heat insulating material 18), and the entire casting is kept at the aging treatment temperature for a predetermined time by the retained heat of the hot-water supply part 14.

  Thus, after the mold 7 is separated, the necessary part is quenched by the local cooling with the cooling medium (see water 15), and the retained heat of the hot-water supply part 14 is effectively used for quenching (solution treatment) and aging. In addition, the aging treatment is performed by covering the casting with the sand molds 1 to 5 and the heat retaining means (see the heat insulating material 18) and effectively using the retained heat of the hot water supply section 14. The T6 treatment can be performed without requiring any heat treatment furnace (aging furnace) and without energy consumption, so that mechanical properties such as product strength can be sufficiently improved. In addition, since the hot water supply portions 8 and 14 are provided, a cavity (shrinkage or nest) is not formed inside the product, and the sand molds 1 to 5 and the core 6 can be reused after the collapse. Of course.

The heat retaining means is set in the heat insulating material 18.
According to this configuration, the heat insulating material 18 such as a glass wool molded body is used as the heat retaining means. That is, a low-temperature heater may be used as the heat retaining means, but if the heat insulating material 18 is used without using a low-temperature heater, power consumption becomes unnecessary and energy saving can be achieved.
Moreover, the quenching temperature is set to 480 to 530 ° C., and the aging treatment is set to be kept within a temperature range of 160 to 240 ° C. for 1 to 2 hours.

  According to this configuration, since the heat treatment conditions are set as described above, sufficient tensile strength and yield strength of the manufactured casting (see the cylinder head portion 13) can be ensured.

  Further, the light alloy casting was set to an aluminum alloy or magnesium alloy cylinder head (see cylinder head portion 13), and the casting surface formed by the mold 7 was set to the combustion chamber side of the cylinder head. Is.

  This configuration has the following effects. That is, the molten metal on the combustion chamber side of the cylinder head in contact with the mold 7 solidifies faster than the sand molds 1 to 5, the metal structure becomes dense, the dimensional accuracy of the casting is increased, and the cylinder head The combustion chamber side is repeatedly heated and cooled during engine operation, but the metal structure is fine and the T6 treatment is applied to improve its mechanical properties, so it is resistant to thermal fatigue cracks. Become.

(Example 2)
Next, another embodiment of a method for producing a light alloy casting using the above-described mold (see FIG. 1) will be described in detail with reference to FIGS.
In the preparation step S11 of the process diagram shown in FIG. 12, the cavity 10 is constituted by the sand mold that forms the feeder part 8 and the mold 7 that is arranged apart from the feeder part 8 and forms part of the cavity 10. A mold (see FIG. 1) is prepared. Next, in the casting step S12 of the process diagram shown in FIG. 12, as shown in FIG. 3, the molten metal 12 of the aluminum alloy (JIS standard AC4B) is transferred from the gate 9 to the cavity 10 through the feeder 8 and the runner 11. When pouring, after the molten aluminum alloy 12 is solidified, as shown in FIG. 4, a cylinder head part 13 and a feeder part 14 are formed as castings.

Next, in the separation step S13 of the process chart shown in FIG. 12, only the mold 7 is separated with the sand molds 1 to 5 and the core 6 left after casting as shown in FIG.
Next, in the quenching step S14 of the process chart shown in FIG. 12, the surface of the cylinder head portion 13 as a casting from which the mold 7 is separated as shown in FIG. Water 15 as a cooling medium is sprayed to locally cool a necessary portion of the casting and quench.

  Here, the quenching temperature is set to 480 to 530 ° C., and water 15 from a plurality of nozzles 16 is sprayed onto the surface corresponding to the combustion chamber of the cylinder head portion 13 that is exposed to the mold surface after the mold 7 is separated. Then, the cylinder head portion 13 is subjected to solution treatment by rapid cooling to 300 ° C. or lower.

  In addition, since the water 15 sprayed from the nozzle 16 to the cylinder head part 13 flows down, the tank 17 which receives this water 15 is provided in quenching station ST2.

  Next, in the continuation step S15 of the process diagram shown in FIG. 12, the adjusted cooling station ST3 shown in FIG. 14 (however, this adjusted cooling station ST3 is not fixed, and the product transport line is set to the station ST3. In this case, mist-like water as the cooling medium for adjusting cooling, that is, mist water 19 is sprayed on the casting surface, and this spraying state is continued for a predetermined time, and then spraying is stopped.

  The timing of stopping the spraying of the fog water 19 is the temperature of the combustion chamber side A (product part A) of the cylinder head 13 and the side B (product part B) close to the hot water supply part 14 in the next aging treatment. Is set to a timing at which recuperation is possible at 160 to 240 ° C. as an aging condition in anticipation of heat transfer from the hot water supply section 14.

  In this example, as shown in FIG. 16 showing the temperature transition of the casting, the spraying time of the water 15 in the quenching step S14 is set to about 5 minutes, and the spraying time of the fog water 19 in the continuation step S15 is about 30 minutes. The temperature a of the product part A is lowered to around 100 ° C., the temperature b of the product part B is lowered to around 150 ° C., and the temperature c of the feeder part 14 is lowered to 300 ° C. or lower.

  Next, in the aging treatment step S16 of the process chart shown in FIG. 12, the cylinder head part 13 and the hot-water supply part 14 as castings are covered with the above-described sand molds 1 to 5 and the heat insulating material 18 as heat retaining means as shown in FIG. Then, the entire casting is kept at the aging treatment temperature for a predetermined time by the heat retained by the hot-water supply unit 14, and the aging treatment is performed.

This aging treatment is set so as to be maintained within a temperature range of 160 to 240 ° C. for 1 to 2 hours.
As shown in FIG. 15, when the cylinder head part 13, the hot water supply part 14, and the sand molds 1 to 5 are placed on the heat insulating material 18 with the sand molds 1 to 5 left on the outer periphery of the casting, the temperature of the casting is externally changed. The product parts A and B can receive heat conduction from the hot-water supply part 14 and can be reheated to a temperature range effective for aging. An aging treatment is performed. In particular, the product part A is subjected to the T6 treatment by both the quenching in the quenching step S14 and the aging treatment in the aging treatment step S16.

  As described above, the light alloy casting manufacturing method of the embodiment shown in FIGS. 12 to 16 is disposed apart from the sand molds 1 to 5 forming the feeder part 8 (see FIG. 1) and the feeder part 8. A preparation step S11 for preparing a mold constituting the cavity 10 with a mold 7 forming a part of the cavity 10, a casting step S12 for casting the molten light alloy 12 into the cavity 10, and a mold 7 after casting Separating step S13, quenching step S14 for quenching the casting by spraying a cooling medium for quenching (see water 15) onto the surface of the casting from which the mold 7 has been separated, and the surface of the casting after quenching. After the cooling medium for adjustment cooling (refer to fog water 19) is sprayed and cooling is continued for a predetermined time, the continuation step S15 for stopping the spraying, and the casting with the sand molds 1 to 5 and the heat retaining means (see the heat insulating material 18). Covering with hot water 14 The entire casting to aging temperature heat is obtained and a aging treatment step S16 to maintain a predetermined time.

  The quenching cooling medium and the adjustment cooling cooling medium sprayed on the surface of the casting are both set to water. In the quenching step S14, the cooling water 15 is sprayed, and in the continuation step S15, mist water (so-called fog) Water) 19 is sprayed. Further, by switching from spraying the cooling water 15 to spraying the fog water 19, the product temperature is controlled to a temperature range (see α in FIG. 16) in which the aging phenomenon can be effectively extracted.

  According to this configuration, after the mold is prepared in the preparation step S11, the light alloy molten metal 12 is cast into the cavity 10 in the casting step S12, and the sand molds 1 to 5 are left after casting in the next separation step S13. In this state, only the mold 7 is separated (released), and in the next quenching step S14, a quenching cooling medium (see water 15) is sprayed on the surface of the casting from which the mold 7 has been separated, and the casting is removed. In the next continuation step S15, after quenching, the cooling medium for adjustment cooling (see fog water 19) is sprayed on the surface of the casting after quenching and cooling is continued for a predetermined time. Then, the spraying is stopped and the next aging is performed. In the processing step S16, the casting (see the cylinder head portion 13) is covered with the sand molds 1 to 5 and the heat retaining means (see the heat insulating material 18), and the entire casting is kept at the aging treatment temperature for a predetermined time by the retained heat of the hot-water supply portion 14. .

  As described above, after the mold 7 is separated, the necessary part is quenched by the local cooling with the cooling medium, and the retained heat of the hot-water supply part 14 is effectively used to easily perform quenching (solution treatment) and aging treatment. Further, the aging treatment is performed by covering the casting (refer to the cylinder head portion 13) with the sand molds 1 to 5 and the heat retaining means (refer to the heat insulating material 18), and effectively utilizing the retained heat of the hot water supply portion 14. Therefore, the T6 treatment can be performed without requiring any heat treatment furnace (aging furnace) and without energy consumption, and the mechanical properties such as the strength of the product can be sufficiently improved.

  Moreover, since the cooling medium for adjusting cooling (see fog water 19) is sprayed in the continuation step S15, this cooling medium can be set to the fog water 19 or the cooling air, and sprayed to the surface of the casting. The fog water 19 is vaporized. As a result, a fixed cooling station is not required, and the casting as the product can be adjusted and cooled during the conveyance of the product, so that the production efficiency can be improved.

  Also in the second embodiment, since the other operations and effects are substantially the same as those of the first embodiment, the same reference numerals are given to the same parts in FIGS. Detailed description is omitted.

(Example 3)
Next, still another embodiment of a method for producing a light alloy casting using the above-described mold (see FIG. 1) will be described in detail with reference to FIGS.
In the preparation step S21 of the process diagram shown in FIG. 17, the cubity 10 is configured by the sand mold that forms the feeder part 8 and the mold 7 that is arranged away from the feeder part 8 and forms a part of the cavity 10. A mold (see FIG. 1) is prepared.

  Next, in the casting step S22 of the process diagram shown in FIG. 17, as shown in FIG. 3, the molten alloy 12 of the aluminum alloy (JIS standard AC4B) is transferred from the gate 9 to the cavity 10 through the feeder 8 and the runner 11. When pouring, after the molten aluminum alloy 12 is solidified, as shown in FIG. 4, a cylinder head part 13 and a feeder part 14 are formed as castings.

Next, in the separation step S23 of the process chart shown in FIG. 17, only the mold 7 is separated with the sand molds 1 to 5 and the core 6 left after casting as shown in FIG.
Next, in the quenching step S24 of the process chart shown in FIG. 17, as a cooling medium on the surface of the cylinder head part 13 as a casting from which the mold 7 is separated as shown in FIG. The required part of the casting is locally cooled and quenched.

  Here, the quenching temperature is set to 480 to 530 ° C. (however, the quenching temperature in the case of casting an aluminum alloy casting), and water 15 from a plurality of nozzles 16 is separated from the mold 7 and exposed to the mold surface. The cylinder head portion 13 is sprayed onto the surface corresponding to the combustion chamber, and rapidly cooled to 300 ° C. or lower to subject the cylinder head portion 13 to a solution treatment.

  In addition, since the water 15 sprayed from the nozzle 16 to the cylinder head part 13 flows down, the tank 17 which receives this water 15 is provided in quenching station ST2.

  Further, as shown in FIG. 19, between the nozzle 16 and the sand molds 1 to 5 and the cylinder head part 13, the water 15 is guided only to the surface of the cylinder head part 13 on the combustion chamber side. A guide plate 20 that prevents direct spraying on 5 may be provided.

  Next, in the submerging step S25 of the process chart shown in FIG. 17, the entire sand molds 1 to 5, the core 6 and the casting are immersed in the water 22 stored in the tank 21 in advance as shown in FIG. As the cylinder head part 13 and the hot water supply part 14 are cooled, the sand molds 1 to 5 and the core 6 are collapsed.

In this case, submergence is started after the time when the hot-water supply unit 14 is solidified for the purpose of avoiding a steam explosion, and the submergence time is set to several seconds.
In this embodiment, the total time of the quenching step S24 and the submerging step S25 is set to about 5 minutes.
Moreover, between the feeder 14 and the product parts A and B (the combustion chamber side of the cylinder head part 13 is the product part A, and the side close to the feeder part 14 of the cylinder head part 13 is the product part B). Submerged in a state where a predetermined temperature difference is maintained.

  After the submerged time of several seconds has elapsed, when the cylinder head part 13 and the hot water supply part 14 as castings are pulled up from the water 22 of the tank 21, the heat of the hot water supply part 14 is gradually transferred to the product parts A and B. .

  Next, in the air blowing step S26 of the process chart shown in FIG. 17, air is blown onto the cylinder head portion 13 and the hot water feeder portion 14 pulled up from the water, and the water 22 adhering thereto is removed.

  Next, in the aging treatment step S27 of the process diagram shown in FIG. 17, the whole of the cylinder head part 13 and the hot-water supply part 14 taken out from the water and subjected to air blowing is shown in FIG. (Glass wool moldings) 18 and 23 are completely covered, and the entire casting (refer to the cylinder head part 13 and the feeder part 14) is kept at the aging treatment temperature for a predetermined time by the retained heat of the feeder part 14, and the artificial aging treatment Apply.

This aging treatment is set so as to be maintained within a temperature range of 160 ° C. to 240 ° C. for 1 to 2 hours.
As shown in FIG. 21, when the entire casting is surrounded by the heat insulating materials 18 and 23, the temperature of the casting can be cut off from the outside world, and the product parts A and B receive heat conduction from the feeder part 14, It can be reheated to a temperature range effective for aging, and is kept for a predetermined time in a soaking state, and aging treatment is performed. In particular, the product part A is subjected to quenching in the quenching step S24 and aging treatment step S27. As a result, the T6 process is performed by both the aging process.

  Thus, the manufacturing method of the light alloy casting of the embodiment shown in FIGS. 17 to 22 includes sand molds 1 to 5 containing a water-soluble binder and formed with a feeder part 8 (see FIG. 1), A preparation step S21 for preparing a mold constituting the cavity 10 with a mold 7 which is arranged apart from the hot water part 8 and forms a part of the cavity 10, and a light alloy molten metal 12 (see FIG. 3) in the cavity 10 is prepared. Casting step S22 for casting, separation step S23 for separating the mold 7 after casting, and quenching step for quenching the casting by spraying a cooling medium (see water 15) onto the surface of the casting from which the mold 7 has been separated. S24, and submerging step S25 for cooling the casting by immersing the sand molds 1 to 5 and the casting (see the cylinder head part and the hot water feeding part 14) in the water 22, and collapsing the sand molds 1 to 5 and the core 6. After removing the casting from the water 22 Castings covered with a heat insulating means (see a heat insulating material 18, 23), in which a aging treatment step S27 to maintain a predetermined time the whole casting to aging temperature in potential heat of risers 14.

In this embodiment, magnesium sulfate hydrate is used as the above-mentioned water-soluble binder.
According to this configuration, after the mold (see FIG. 1) is prepared in the preparation step S21, the light alloy molten metal 12 is cast into the cavity 10 in the casting step S22, and after casting in the next separation step S23. Only the mold 7 is separated (released) with the sand molds 1 to 5 left, and in the next quenching step S24, a cooling medium (see water 15) is sprayed on the surface of the casting from which the mold 7 has been separated. The casting is quenched, and in the next submerging step S25, the sand molds 1 to 5 and the casting are immersed in the water 22 to cool the casting, and the sand molds 1 to 5 and the core 6 that are molded with the water-soluble binder are collapsed. In the next aging treatment step S27, after the casting is taken out from the water 22, the casting is covered with heat retaining means (see heat insulating materials 18 and 23), and the entire casting is subjected to the aging treatment temperature by the retained heat of the hot water feeder section 14. Keep for a predetermined time.

  As described above, after the mold 7 is separated, the necessary part is quenched by the local cooling with the cooling medium, and the retained heat of the hot-water supply part 14 is effectively used to easily perform quenching (solution treatment) and aging treatment. Further, the aging treatment is performed by covering the casting with the heat retaining means (see the heat insulating materials 18 and 23) and effectively using the retained heat of the hot-water supply unit 14, so that a heat treatment furnace (aging furnace) is used. The T6 treatment can be performed without necessity and without energy consumption, and the mechanical properties such as strength of the product can be sufficiently improved.

  Moreover, since the sand molds 1 to 5, the core 6 and the casting (see the cylinder head part 13 and the hot water feeder part 14) are immersed in water in the submergence step S25, the sand molds 1 to 5 and the core formed with a water-soluble binder are used. 6 can be achieved, and the excess temperature of the hot-water feeder 14 can be lowered by submerging, so that the cooling time of the casting from the quenching step S24 to the aging treatment step S27 can be efficiently and greatly shortened. You can.

  Also in the third embodiment, since the other operations and effects are substantially the same as those of the previous embodiment, the same reference numerals are given to the same portions in FIGS. Description is omitted.

Example 4
Next, still another embodiment of a method for producing a light alloy casting using the above-described mold (see FIG. 1) will be described in detail with reference to FIGS.

  In the preparation step S31 of the process chart shown in FIG. 23, the cubity 10 is configured by the sand mold that forms the feeder part 8 and the mold 7 that is arranged away from the feeder part 8 and forms part of the cavity 10. A mold (see FIG. 1) is prepared.

However, in this embodiment, a water-insoluble gas-curable binder is used in place of the water-soluble binder without using a water-soluble binder for forming the sand molds 1 to 5 and the core 6.
That is, the sand molds 1 to 5 and the core 6 are formed by a cold box molding method, and contain a gas curable binder (a main material phenol resin and a curing agent polyisocyanate) that is cured with an amine gas.

Since this binder is insoluble in water, the sand molds 1 to 5 and the core 6 do not collapse with water.
As the water-insoluble curable binder, a thermosetting binder containing a phenolic resin as a main material and hexamethylenetetramine as a curing agent can be used. Since it is used and cured, it is preferable because the dimensional accuracy of the mold is high and the molding time is short.

  Next, in the casting step S32 of the process diagram shown in FIG. 23, as shown in FIG. 3, the molten metal 12 of the aluminum alloy (JIS standard AC4B) is transferred from the gate 9 to the cavity 10 through the feeder 8 and the runner 11. When pouring, after the molten aluminum alloy 12 is solidified, as shown in FIG. 4, a cylinder head part 13 and a feeder part 14 are formed as castings.

Next, in the separation step S33 of the process chart shown in FIG. 23, only the mold 7 is separated with the sand molds 1 to 5 and the core 6 left after casting as shown in FIG.
Next, in the quenching step S34 of the process chart shown in FIG. 23, the above-described sand molds 1 to 5, the core 6, and the cylinder head part 13 as a casting are brought together with the hot water part 14 into the tank 24 shown in FIGS. It is immersed in high temperature water 25 at 100 ° C. or less (preferably 90 to 99 ° C.), and quenching is performed to cool the surface of the casting from which the mold 7 is separated.

In this case, since the lifting device 26 shown in FIGS. 24 and 25 is used, the structure of the lifting device 26 will be described.
The elevating device 26 is fixed to one side wall of the tank 24, and a plurality of guide rods 27 extending in the vertical direction, a drive cylinder 28 including a hydraulic cylinder provided along the guide rod 27, and the like. A support frame 30 provided at the upper end of the piston rod 29 of the drive cylinder 28 and moving up and down while being guided by the plurality of guide rods 27, and a support member 31 provided on the side of the support frame 30 corresponding to the tank 24. And a pedestal 32 attached horizontally to the lower portion of the support member 31 and a pair of stoppers 33, 33 fixed to the upper portion of the pedestal 32, and between the pair of stoppers 33, 33 above the pedestal 32 As shown in FIG. 24, the sand molds 1 to 5 and the casting are gripped by a robot and set up so as not to be displaced, and the piston rod 2 of the drive cylinder 28 is set. The sand molds 1 to 5, the core 6 and the casting are immersed in the high-temperature water 25 as shown in FIG. 25 through the cradle 32 guided by the guide rod 27. Yes.

In this quenching step S34, hot water 25 as a cooling medium is brought into contact with the surface of the cylinder head portion 13 as a casting from which the mold 7 is separated, that is, the surface on the combustion chamber side of the cylinder head, thereby locally cooling the necessary portion of the casting. And quench. This quenching with high-temperature water prevents a large temperature difference from occurring in the cylinder head portion 13 and a high residual stress.
Here, the quenching temperature is set to 480 to 530 ° C. (however, the quenching temperature in the case of casting an aluminum alloy casting), and the mold 7 is separated from the hot water 25 in the tank 24 shown in FIG. The cylinder head part 13 is brought into contact with the surface corresponding to the combustion chamber of the cylinder head part 13 exposed on the surface, and rapidly cooled to 300 ° C. or lower to subject the cylinder head part 13 to a solution treatment.

  When a predetermined time (about 15 minutes) has elapsed since the start of submersion shown in FIG. 26, the drive cylinder 28 is operated to raise the cradle 32, and the sand molds 1 to 5, the core 6 and the casting are pulled up from the tank 24. The sand molds 1 to 5, the core 6 and the casting are put into the next aging treatment step by a robot. Note that there is almost no cooling due to water intrusion from the sand molds 1 to 5 when the sand molds 1 to 5, the core 6 and the casting are immersed in water as shown in FIG. When the cylinder head part 13 and the hot metal part 14 as castings are pulled up from the high temperature water 25 of the tank 24, the heat of the hot water part 14 is gradually transmitted to the product parts A and B.

Next, in the aging treatment step S35 of the process chart shown in FIG. 23, the cylinder head part 13 and the hot water supply part 14 pulled up from the water are covered with the sand molds 1 to 5 and the heat insulating material 18 as shown in FIG. The entire casting (refer to the cylinder head part 13 and the hot water supply part 14) is kept at the aging treatment temperature for a predetermined time by the retained heat of the hot water part 14, and the artificial aging treatment is performed.
This aging treatment is set so as to be maintained within a temperature range of 160 ° C. to 240 ° C. for 1 to 2 hours.

  As shown in the characteristic diagram of the temperature transition of each part a, b, c in FIG. 26, when the entire casting is surrounded by the sand molds 1 to 5 and the heat insulating material 18 (see FIG. 7), the temperature of the casting is cut off from the outside. The product parts A and B can be reheated to a temperature range effective for aging by receiving heat conduction from the hot water supply part 14, and are maintained for a predetermined time under a soaking condition, In particular, the product part A is subjected to the T6 treatment by both the quenching in the quenching step S34 and the aging treatment in the aging treatment step S35.

  As described above, the light alloy casting manufacturing method according to the embodiment shown in FIGS. 23 to 26 includes a sand mold 1 to 5 containing a water-insoluble gas curable binder and formed with a feeder part 8; A preparation step S31 for preparing a mold constituting the cavity 10 with a mold 7 which is arranged away from the feeder 8 and forms part of the cavity 10, and a casting step for casting the molten light alloy 12 into the cavity 10 S32, a separation step S33 for separating the mold 7 after casting, a quenching step S34 for cooling the surface of the casting from which the mold 7 has been separated by immersing the sand molds 1 to 5 and the casting in the high-temperature water 25, and After the sand molds 1 to 5 and the casting are taken out from the high-temperature water 25, the casting is covered with the sand molds 1 to 5 and the heat insulating material 18, and the entire casting is kept at the aging treatment temperature for a predetermined time by the retained heat of the hot water feeder section 14. And processing step S35.

  According to this configuration, in the preparation step S31, a mold including the cavity 10 is configured by both the sand molds 1 to 5 and the mold 7, and in the casting step S32, the light alloy molten metal 12 is cast into the cavity 10, In the next separation step S33, only the mold 7 is separated (released) with the sand molds 1 to 5 remaining after casting, and in the next quenching step S34, the sand molds 1 to 5 and the casting are put into the high-temperature water 25. The casting surface from which the mold 7 has been separated is cooled to quench the casting, and after the sand molds 1 to 5 and the casting are taken out from the high temperature water 25 in the next aging treatment step S35, the casting is kept warm. Are covered with the heat insulating material 18 and the sand molds 1 to 5, and the entire casting is kept at the aging treatment temperature for a predetermined time by the retained heat of the hot-water supply portion 14.

  Thus, after the mold 7 is separated, the sand molds 1 to 5 and the casting are immersed in water to cool the surface of the casting from which the mold 7 is separated, and necessary parts are quenched, and then the sand molds 1 to 5 and An aging treatment can be achieved by effectively using the heat retained in the hot-water supply part 14 under the condition that the casting is covered with the heat insulating material 18, and the aging treatment described above further comprises casting the sand molds 1 to 5 and the heat insulating material. 18 so that the heat stored in the hot-water supply unit 14 is effectively used, so that the heat treatment furnace (aging furnace) is not required and energy is not consumed, and the T6 treatment is performed to obtain the strength of the product. It is possible to sufficiently improve the mechanical properties.

  Moreover, since the sand molds 1 to 5 and the casting are immersed in the high-temperature water 25 of 100 ° C. or less, the excess temperature of the hot-water supply part 14 can be lowered with water, so the casting from the quenching step S34 to the aging treatment step S35. The cooling time can be shortened efficiently.

  In short, in the embodiment shown in FIGS. 23 to 26, even if the sand molds 1 to 5 and the casting are immersed in the high temperature water 25 of the tank 24, the mold 7 is cooled from the separated casting surface and quenched. After that, the casting is covered with the sand molds 1 to 5 and the heat insulating material 18, and the entire casting is kept at the aging treatment temperature for a predetermined time by the retained heat of the feeder 14, so that the aging treatment can be performed. is there. In addition, in Example 4, since there are substantially the same operations and effects as the previous examples in the other points, the same reference numerals are given to the same parts in FIGS. Detailed description thereof is omitted.

  In addition, although the aluminum alloy as a light alloy was illustrated in the said Example, it may replace with an aluminum alloy and may use a magnesium alloy (JIS specification MC1). In this case, it is desirable to set the quenching temperature to 380 to 390 ° C and the artificial aging temperature to 220 to 260 ° C.

In the correspondence between the configuration of the present invention and the above-described embodiment,
The casting of the present invention corresponds to the cylinder head portion 13 and the hot water feeder portion 14,
Similarly,
The cooling medium corresponds to water 15 and hot water 25,
The cooling medium for quenching corresponds to water 15,
The cooling medium for adjusting cooling corresponds to the fog water 19,
The heat retaining means corresponds to the heat insulating materials 18 and 23,
Water-soluble binder corresponds to magnesium sulfate hydrate,
The present invention is not limited to the configuration of the above-described embodiment.

Sectional drawing of the casting_mold | template used for the manufacturing method of the light alloy casting of this invention Process diagram showing the light alloy casting manufacturing method Explanatory drawing during pouring Explanatory drawing of casting process Illustration of separation process Explanatory drawing of quenching process and continuation process Explanatory drawing of aging treatment process Characteristic diagram showing temperature transition of castings Characteristic diagram showing measurement results of tensile strength Characteristic chart showing measurement results of 0.2% proof stress Characteristic diagram showing measurement results of elongation at break Process drawing showing another embodiment of a method for producing a light alloy casting Explanatory drawing of quenching process Illustration of continuation process Explanatory drawing of aging treatment process Characteristic diagram showing temperature transition of castings Process drawing showing still another embodiment of a method for producing a light alloy casting Explanatory drawing of quenching process Explanatory drawing showing another embodiment of the quenching process Explanatory drawing of submerged process Explanatory drawing of aging treatment process Characteristic diagram showing temperature transition of castings Process drawing showing still another embodiment of a method for producing a light alloy casting Explanatory drawing of lifting device Explanatory drawing showing the quenching process by immersion in water Characteristic diagram showing temperature transition of castings

Explanation of symbols

DESCRIPTION OF SYMBOLS 1-5 ... Sand mold 7 ... Mold 8 ... Hot water supply part 10 ... Cavity 13 ... Cylinder head part (casting)
14 ... Hot water (casting)
18, 23 ... Insulating material (heat insulation means)
S1, S11, S21, S31 ... Preparation steps S2, S12, S22, S32 ... Casting steps S3, S13, S23, S33 ... Separation steps S4, S14, S24, S34 ... Quenching steps S5, S15 ... Continue steps S6, S16, S27, S35 ... Aging treatment step S25 ... Submerged step

Claims (8)

A preparation step of preparing a mold constituting the cavity with a sand mold that forms the feeder part and a mold that is arranged apart from the feeder part and forms a part of the cavity;
A casting process for casting a light alloy molten metal into the cavity;
A separation step of separating the mold after casting;
A quenching process in which the cooling medium is brought into contact with the surface of the casting from which the mold is separated, and the casting is quenched;
A light alloy casting manufacturing method comprising: an aging treatment step of covering a casting with the sand mold and the heat retaining means, and maintaining the entire casting at an aging treatment temperature for a predetermined time with heat retained in the hot water feeder. A preparation step of preparing a mold constituting the cavity with a sand mold that forms the feeder part and a mold that is arranged apart from the feeder part and forms a part of the cavity;
A casting process for casting a light alloy molten metal into the cavity;
A separation step of separating the mold after casting;
A quenching process in which a cooling medium is sprayed onto the surface of the casting from which the mold has been separated to quench the casting;
A continuation step of stopping the spraying after continuing the spraying state of the cooling medium for a predetermined time;
A light alloy casting manufacturing method comprising: an aging treatment step of covering a casting with the sand mold and the heat retaining means, and maintaining the entire casting at an aging treatment temperature for a predetermined time with heat retained in the hot water feeder. A preparation step of preparing a mold that constitutes a cavity with a sand mold that forms a feeder part and a mold that is arranged apart from the feeder part and forms a part of the cavity;
A casting process for casting a light alloy molten metal into the cavity;
A separation step of separating the mold after casting;
A quenching step of quenching the casting by spraying a quenching cooling medium on the surface of the casting from which the mold has been separated;
A continuous process of stopping the spraying after spraying a cooling medium for adjusting cooling to the surface of the casting after quenching and continuing cooling for a predetermined time;
A light alloy casting manufacturing method comprising: an aging treatment step of covering a casting with the sand mold and the heat retaining means, and maintaining the entire casting at an aging treatment temperature for a predetermined time with heat retained in the hot water feeder. A preparation step for preparing a mold that forms a cavity with a sand mold that contains a water-soluble binder and a hot water portion is formed, and a mold that is arranged apart from the hot water portion and forms a part of the cavity;
A casting process for casting a light alloy molten metal into the cavity;
A separation step of separating the mold after casting;
A quenching process in which a cooling medium is sprayed onto the surface of the casting from which the mold has been separated to quench the casting;
Submerging the sand mold and casting in water to cool the casting and submerge the sand mold,
A light alloy casting manufacturing method comprising: an aging treatment step of covering a casting with heat-retaining means after removing the casting from the water, and maintaining the entire casting at an aging treatment temperature for a predetermined time by heat retained in a feeder part. Preparation for preparing a mold that forms a cavity with a sand mold that contains a water-insoluble curable binder and has a feeder part formed, and a mold that is arranged away from the feeder part and forms a part of the cavity Process,
A casting process for casting a light alloy molten metal into the cavity;
A separation step of separating the mold after casting;
A quenching step of cooling the surface of the casting from which the mold is separated by immersing the sand mold and the casting in water;
After taking out the sand mold and the casting from the water, the casting is covered with the sand mold and the heat retaining means, and an aging treatment step is performed for keeping the entire casting at the aging treatment temperature for a predetermined time by the retained heat of the feeder part. Production method. The method for manufacturing a light alloy casting according to any one of claims 1 to 5, wherein the heat retaining means is set as a heat insulating material. The light alloy casting is set to an aluminum alloy casting,
Set the quenching temperature to 480-530 ° C,
The method for producing a light alloy casting according to any one of claims 1 to 5, wherein the aging treatment is set to be maintained within a temperature range of 160 to 240 ° C for 1 to 2 hours. The light alloy casting is set to a cylinder head made of aluminum alloy or magnesium alloy,
The method for producing a light alloy casting according to any one of claims 1 to 5, wherein a surface of the casting formed by the mold is set on a combustion chamber side of the cylinder head.

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