CN115254949A - A kind of titanium and titanium alloy round ingot direct rolling blanking method - Google Patents

Abstract

The invention provides a method for direct rolling and billeting of titanium and titanium alloy round ingots, which specifically includes the following steps: Step 1: demoulding the titanium and titanium alloy round ingots after melting, solidification and cooling, and grinding the surface to remove surface oxides Then, the billet to be heated is obtained; step 2: transfer the billet to be heated to a heating furnace, and after heating to a set temperature, carry out a heat preservation treatment to obtain a billet to be rolled; step 3: put the billet to be rolled into a two-roll mill, along the The continuous rolling of bar and wire rod is obtained by reciprocating rolling in the length direction of the round ingot, wherein each rolling is multi-pass rolling, and between two rollings, the billet adjustment and straightening process are used to ensure that the billet to be rolled is guaranteed. The flatness of the blank. The invention solves the technical problems such as low production efficiency, unstable forging quality and finished product rate, etc. that the continuous rolling blank of the bar needs to be processed by forging and blanking for many times in the prior art.

Description

A kind of titanium and titanium alloy round ingot direct rolling blanking method

technical field

The invention relates to the technical field of metal plastic forming, in particular to a method for direct rolling billeting of titanium and titanium alloy round ingots.

Background technique

Titanium and titanium alloys have the characteristics of high strength and good corrosion resistance, and are widely used in aerospace, marine equipment and other fields. However, titanium and titanium alloys have poor plasticity and high process costs. In recent years, the research on titanium alloys has gradually developed into the field of low process cost and high performance. Therefore, the high-efficiency production of titanium and titanium alloys is the only way for titanium to develop widely.

圆铸锭开坯为180×180mm连轧方坯需要五个锻造火次，多火次锻造难以保证方坯的平直度，生产工艺流程较长，生产效率低，工序能耗较大，并且锻造工艺的制定依赖现场工程技术人员生产实际操作经验，加之锻造过程操作复杂，钛合金锻件质量和成品率难以全面保证和稳定，开坯锻造的好与坏以及锻造水平的高低直接影响到后续的产品质量，以上等等因素严重的影响了钛材的广泛发展和应用。Continuous rolling of titanium and titanium alloy rods and wires is obtained by vacuum consumable arc melting of titanium and titanium alloy round ingots. And inclusions, etc., to make the billet structure and properties uniform. At present, the general process of billeting of large titanium and titanium alloy ingots is to form a forging billet through multi-fire billet forging, and the forging billet process is a forging process that includes multiple passes, multiple fires, and multiple processes, such as

The billet of the round ingot is 180×180mm continuous rolling billet needs five forging fires, multi-fire forging is difficult to ensure the straightness of the billet, the production process is long, the production efficiency is low, the energy consumption of the process is large, and The formulation of the forging process depends on the actual production experience of the on-site engineers and technicians. In addition, the forging process is complex, and the quality and yield of titanium alloy forgings are difficult to fully guarantee and stabilize. The quality of the blank forging and the forging level directly affect the subsequent Product quality, the above factors have seriously affected the extensive development and application of titanium materials.

Contents of the invention

Aiming at the defects and insufficiencies of existing titanium and titanium alloy bar continuous rolling blank processing technology, the present invention provides a titanium and titanium alloy round ingot direct rolling blanking method, which does not use forging blanking, but uses a two-roll mill Billet rolling method, smelting ingot can be EB furnace, vacuum consumable arc smelting, electroslag furnace and other single or combined multiple smelting methods, which solves the problem that the bar continuous rolling billet in the prior art needs to be forged by multiple fires. Billet processing has a long production process and low production efficiency, and it is difficult to fully guarantee and stabilize the quality and yield of titanium and titanium alloy forgings, which affects the extensive development and application of titanium materials.

The technical means adopted in the present invention are as follows:

A method for direct rolling billeting of titanium and titanium alloy round ingots, specifically comprising the following steps:

Step 1: Demoulding the titanium and titanium alloy round ingot after smelting, solidification and cooling, and grinding the surface to remove surface oxides to obtain a billet to be heated;

Step 2: Transfer the billet to be heated to the heating furnace, heat it to the set temperature, and perform heat preservation treatment to obtain the billet to be rolled;

Step 3: Put the billet to be rolled into a two-roll rolling mill, and roll it back and forth multiple times along the length direction of the round ingot to obtain a continuous rolling billet for rods and wires, wherein each rolling is multi-pass rolling, and two The flatness of the billet to be rolled is ensured through the billet turning adjustment and straightening process between the second rolling.

Further, the set temperature is 850-1120°C, the holding time is 120min-240min, and the feeding temperature of the heating furnace is 600°C-700°C.

Further, in step 3, the amount of deformation per pass of each rolling is 3%-15%, and the cumulative deformation amount in one direction reaches 30%-40%. Before the next rolling, the billet to be rolled is turned 90° The billet is continuously rolled on the narrow side, and rolled repeatedly until the target size of the continuous rolling billet is reached.

Further, in step three, the straightening process refers to clamping the billet to be rolled by side guide plates during the rolling process to ensure straightness.

Further, in the third step, the rolling speed of the rolling process is controlled at 0.2m/s-9m/s, and the rolling speed is accelerated with the increase of the rolling times.

Further, in step 1, the heating furnace can simultaneously heat at least ten billets to be heated.

Further, it is used to prepare billets and slabs of different cross-sectional sizes.

时，步骤三中进行往复多次轧制得到棒线材连轧坯的时间为5-18min。Further, when the weight of the billet to be heated is 3-6 tons, the size of the circular section is

, the time for performing reciprocating multiple rolling in step 3 to obtain continuous rolling billets of rods and wires is 5-18 minutes.

时，步骤三中进行往复多次轧制得到棒线材连轧坯的时间为5min。Further, when the weight of the billet to be heated is 2-3 tons, the size of the circular section is

, the time for performing reciprocating multiple rolling in step 3 to obtain continuous rolling billets of rods and wires is 5 minutes.

Compared with the multi-fire forging blanking technology, the present invention has the following advantages:

1. The titanium and titanium alloy rods and wires provided by the present invention are continuous rolling billets and direct rolling blanking methods, using titanium alloy round ingots as materials, the ingots are not limited by the smelting process, and can be vacuum consumable arc melting, vacuum self-consumption arc melting, vacuum self-consumption Large-scale titanium and titanium alloy round ingots smelted by a single or combined electron beam cooling bed furnace, the heating furnace can heat more than ten billets at the same time, improve processing efficiency, and the heating temperature is low, reducing gas consumption.

2. The continuous rolling and direct rolling blanking method of titanium and titanium alloy rods and wires provided by the present invention, the circular casting ingot is directly rolled and fired to form a billet, which avoids titanium chips generated on the surface of the forging after reciprocating heating, improves the yield, and can significantly improve production Efficiency, while the length of the round ingot is not limited.

3. The method for continuous rolling and direct rolling of titanium and titanium alloy rods and wires provided by the present invention has slow temperature drop in the rolling process, strong deformation continuity, and no surface indentation and cracking of direct-rolled square billets and slabs, which greatly improves The surface quality can be widely used in aerospace and other fields, and the service life is long.

Based on the above reasons, the present invention can be widely promoted in the field of metal plastic forming.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained according to these drawings without any creative effort.

Fig. 1 is a schematic diagram of the process flow of the direct rolling blanking method of the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is only some embodiments of the present invention, but not all embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and in no way taken as limiting the invention, its application or uses. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As shown in Fig. 1, the present invention provides a kind of titanium and titanium alloy round ingot direct-rolling blanking method, specifically comprises the following steps:

Step 1: Demoulding the titanium and titanium alloy round ingot after smelting, solidification and cooling, and grinding the surface to remove surface oxides to obtain a billet to be heated;

Step 2: Transfer the billet to be heated to the heating furnace, heat it to the set temperature, and perform heat preservation treatment to obtain the billet to be rolled;

Step 3: Put the billet to be rolled into a two-roll rolling mill, and roll it back and forth multiple times along the length direction of the round ingot to obtain a continuous rolling billet for rods and wires, wherein each rolling is multi-pass rolling, and two The flatness of the billet to be rolled is ensured through the billet turning adjustment and straightening process between the second rolling.

Further, the set temperature is 850-1120°C, the holding time is 120min-240min, and the feeding temperature of the heating furnace is 600°C-700°C.

Further, in step 3, the amount of deformation per pass of each rolling is 3%-15%, and the cumulative deformation amount in one direction reaches 30%-40%. Before the next rolling, the billet to be rolled is turned 90° The billet is continuously rolled on the narrow side, and rolled back and forth multiple times until the target bar and wire continuous rolling billet size is reached;

The specific heat capacity of titanium alloy is small, and it is heated unevenly during the rolling process, and defects such as cracks are prone to occur, thereby affecting the quality of titanium alloy. Effectively eliminate metallurgical defects such as coarse as-cast structure, voids, porosity and inclusions inside the billet, and make the billet structure and properties uniform.

Further, in step three, the straightening process refers to clamping the billet to be rolled by the side guide plate to ensure the straightness during the rolling process; There will be bending in the middle. At this time, the side guide plate should be used to clamp and restore the straightness, and the feeding and rolling will continue after straightening.

Further, in the third step, the rolling speed of the rolling process is controlled at 0.2m/s-9m/s, and the rolling speed is accelerated with the increase of the rolling times.

Further, in step 1, the heating furnace can simultaneously heat at least ten billets to be heated.

Further, it is used to prepare billets and slabs of different cross-sectional sizes.

时，步骤三中进行往复多次轧制得到棒线材连轧坯的时间为5-18min。Further, when the weight of the billet to be heated is 3-6 tons, the size of the circular section is

, the time for performing reciprocating multiple rolling in step 3 to obtain continuous rolling billets of rods and wires is 5-18 minutes.

时，步骤三中进行往复多次轧制得到棒线材连轧坯的时间为5min。Further, when the weight of the billet to be heated is 2-3 tons, the size of the circular section is

, the time for performing reciprocating multiple rolling in step 3 to obtain continuous rolling billets of rods and wires is 5 minutes.

Further, titanium and titanium alloy round ingots are produced by vacuum consumable arc melting or by single or combined melting in electron beam cooling hearth furnace and vacuum consumable furnace.

Example 1

直轧开坯具体包括以下步骤：This embodiment takes the 3-ton class TC4 titanium alloy round ingot as an example to illustrate the method of the present invention by direct rolling. The TC4 titanium alloy round ingot is obtained by melting in a vacuum consumable electric arc furnace twice, and the ingot size is for

The billet opening by direct rolling specifically includes the following steps:

Step 1: Demoulding the TC4 titanium alloy round ingot after smelting, solidification and cooling, and grinding the surface to remove surface oxides to obtain a billet to be heated;

Step 2: Transfer the billet to be heated to a heating furnace, heat it to 1120°C, and keep it warm for 180 minutes to obtain the billet to be rolled;

Step 3: Put the billet to be rolled into a two-roll rolling mill, and roll it back and forth multiple times along the length direction of the round ingot to obtain a continuous rolling billet for rods and wires. Each rolling includes five passes, and the initial rolling The speed is 0.5m/s, the deformation of the first three passes is 3-5%, and the deformation of the last two passes is 8-10%. After the cumulative deformation reaches 40%, the billet to be rolled is turned over at 90° , continue to carry out five-pass rolling on the narrow side, the deformation of the first three passes is 3 to 5%, the deformation of the last two passes is 8 to 10%, and after the cumulative deformation reaches 30%, continue to roll the blank. Turn over 90°, then increase the rolling speed to 2.8m/s, and continue rolling. During the whole rolling process, the billet to be rolled is clamped by the side guide plate to ensure straightness, until the size of 180mm×540mm×L is obtained. TC4 slab; the whole rolling process takes 5 minutes by adopting the method provided by the invention, compared with the average time-consuming 60 minutes of the forging method, the time is reduced by more than 10 times, and the production efficiency is significantly improved.

The TC4 slab finally obtained in this example has a flat shape, a smooth surface and no cracks, and the microstructure is a fine and uniform short rod-shaped α phase, and the α phase is about 8um to 22um. The grain breakage of the TC4 titanium alloy slab after rolling is relatively Well, the tissue is even.

Example 2

直轧开坯具体包括以下步骤：This embodiment takes the 3-ton TC4 titanium alloy round ingot as an example to illustrate the method of the present invention. The TC4 titanium alloy round ingot is smelted through the double process of electron beam cooling bed furnace+vacuum consumable furnace Obtained, the ingot size is

The billet opening by direct rolling specifically includes the following steps:

Step 1: Demoulding the TC4 titanium alloy round ingot after smelting, solidification and cooling, and grinding the surface to remove surface oxides to obtain a billet to be heated;

Step 2: Transfer the billet to be heated to a heating furnace, heat it to 1120°C, and keep it warm for 180 minutes to obtain the billet to be rolled;

Step 3: Put the billet to be rolled into a two-roll rolling mill, and roll it back and forth multiple times along the length direction of the round ingot to obtain a continuous rolling billet for rods and wires. Each rolling includes five passes, and the initial rolling The speed is 0.3m/s, the deformation of the first three passes is 3-5%, and the deformation of the last two passes is 8-10%. After the cumulative deformation reaches 40%, the billet to be rolled is turned over at 90° , continue to carry out five-pass rolling on the narrow side, the deformation of the first three passes is 3 to 5%, the deformation of the last two passes is 8 to 10%, and after the cumulative deformation reaches 30%, continue to roll the blank. Turn over 90°, then increase the rolling speed to 3.5m/s, and continue rolling. During the whole rolling process, the billet to be rolled is clamped by the side guide plate to ensure straightness, until the size of 180mm×180mm×L is obtained. TC4 rectangular billet; the whole rolling process takes 8 minutes, and the whole rolling process takes 8 minutes by adopting the method provided by the present invention, compared with the average time-consuming 120 minutes of the forging method, the time is reduced by 15 times, and the production efficiency is significantly improved .

The surface of the TC4 billet finally prepared in this example is smooth without cracks, and the microstructure is fine and uniform short rod-shaped α phase, and the α phase is about 5um to 12um.

Example 3

直轧开坯具体包括以下步骤：This embodiment takes the 3-ton TB9 titanium alloy round ingot as an example to illustrate the method of the present invention. The TB9 titanium alloy round ingot is smelted through the dual process of electron beam cooling bed furnace+vacuum consumable furnace Obtained, the ingot size is

The billet opening by direct rolling specifically includes the following steps:

Step 1: Demoulding the TB9 titanium alloy round ingot after smelting, solidification and cooling, and grinding the surface to remove surface oxides to obtain a billet to be heated;

Step 2: Transfer the billet to be heated to a heating furnace, heat it to 920°C, and keep it warm for 180 minutes to obtain the billet to be rolled;

Step 3: Put the billet to be rolled into a two-roll rolling mill, and roll it back and forth multiple times along the length direction of the round ingot to obtain a continuous rolling billet for rods and wires. Each rolling includes five passes, and the initial rolling The speed is 1m/s, the deformation amount of the first three passes is 3-5%, and the deformation amount of the last two passes is 8-10%. After the cumulative deformation amount reaches 30%, the billet to be rolled is turned over at 90°. Continue to carry out five-pass rolling on the narrow side, the deformation of the first three passes is 3-5%, and the deformation of the last two passes is 8-10%. After the cumulative deformation reaches 30%, continue to turn the billet 90°, then increase the rolling rate to 7m/s, and continue rolling. During the whole rolling process, the billet to be rolled is clamped by the side guide plate to ensure straightness, until a TB9 length of 180mm×180mm×L is obtained. Billet; the whole rolling process takes 10 minutes, the surface of the prepared TB9 billet is smooth without cracks, the microstructure is β structure, and the average grain size is about 68um. uniform.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (9)

1. a titanium and titanium alloy round ingot direct rolling blanking method is characterized in that, specifically comprises the following steps: Step 1: Demoulding the titanium and titanium alloy round ingot after smelting, solidification and cooling, and grinding the surface to remove surface oxides to obtain a billet to be heated; Step 2: Transfer the billet to be heated to the heating furnace, heat it to the set temperature, and perform heat preservation treatment to obtain the billet to be rolled; Step 3: Put the billet to be rolled into a two-roll rolling mill, and roll it back and forth multiple times along the length direction of the round ingot to obtain a continuous rolling billet for rods and wires, wherein each rolling is multi-pass rolling, and two The flatness of the billet to be rolled is ensured through the billet turning adjustment and straightening process between the second rolling. 2. The method for direct rolling billeting of titanium and titanium alloy round ingots according to claim 1, characterized in that in step 2, the set temperature is 850-1120°C, the holding time is 120min-240min, and the heating furnace feed temperature It is 600℃～700℃. 3. The billet opening method for direct rolling of titanium and titanium alloy round ingots according to claim 1, characterized in that, in step 3, the amount of deformation per pass of each rolling is 3%-15%, and the cumulative deformation in one direction When the amount reaches 30%-40%, before the next rolling, the slab to be rolled is turned over at 90°, and the rolling is continued on the narrow side, and the rolling is reciprocated several times until the target bar and wire continuous rolling slab size is reached. 4. The method for billeting of titanium and titanium alloy round ingots by direct rolling according to claim 1, characterized in that in step 3, the straightening process refers to clamping the billet to be rolled by side guide plates during the rolling process to ensure flatness. Straightness. 5. The titanium and titanium alloy round ingot direct rolling blanking method according to claim 1, characterized in that, in step 3, the rolling speed of the rolling process is controlled at 0.2m/s～9m/s, and the rolling The speed increases with the increase of rolling times. 6. The method for direct rolling billeting of titanium and titanium alloy round ingots according to claim 1, characterized in that, in step 1, the heating furnace can simultaneously heat at least ten billets to be heated. 7. The method for direct rolling billeting of titanium and titanium alloy round ingots according to claim 1, characterized in that it is used to prepare billets and slabs of different cross-sectional sizes. 8. The titanium and titanium alloy round ingot direct rolling blanking method according to claim 1, characterized in that, when the weight of the billet to be heated is 3-6 tons, the size of the circular section is

, the time for performing reciprocating multiple rolling in step 3 to obtain continuous rolling billets of rods and wires is 5-18 minutes. 9. The titanium and titanium alloy round ingot direct rolling blanking method according to claim 1, characterized in that, when the weight of the billet to be heated is 2-3 tons, the size of the circular section is

, the time for performing reciprocating multiple rolling in step 3 to obtain continuous rolling billets of rods and wires is 5 minutes.

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