CN108311577A - A kind of magnalium two-layer compound cylindrical member and its stepped spinning moulding process - Google Patents

Abstract

The invention provides a magnesium-aluminum double-layer composite cylindrical part and its staggered pitch spinning forming process, which belongs to the technical field of composite cylindrical part forming spinning processing, including mechanical processing to obtain an aluminum alloy outer cylinder and a magnesium alloy inner cylinder, and grinding and cleaning the aluminum alloy outer cylinder and the magnesium alloy inner cylinder, and perform staggered spinning processing on the aluminum alloy outer cylinder and the magnesium alloy inner cylinder. The invention adopts the staggered spinning technology to prepare the magnesium-aluminum double-layer composite cylindrical part. The composite cylindrical part uses aluminum alloy as the outer layer material to improve the plasticity and corrosion resistance of the cylindrical part while maintaining its light weight. big advantage.

Description

A magnesium-aluminum double-layer composite cylindrical part and its staggered pitch spinning forming process

technical field

The invention relates to the technical field of forming and spinning processing of composite cylindrical parts, in particular to a magnesium-aluminum double-layer composite cylindrical part and a staggered pitch spinning forming process thereof.

Background technique

Magnesium alloys are known as environmentally friendly and energy-saving materials in the 21st century due to their advantages such as low density, high specific strength and specific stiffness, excellent dimensional stability, and abundant resources. In recent years, magnesium alloys have become a research hotspot for many scholars. However, since the magnesium alloy has a close-packed hexagonal crystal structure, there is only one slip plane (0001) at room temperature and there are three close-packed directions on this surface, that is, three slip systems. The small number of slip systems leads to plastic deformation of the magnesium alloy at room temperature. Difficult; in addition, magnesium alloys are easily oxidized to form magnesium oxide or magnesium hydroxide on the surface, and these two substances are very easy to react with water or pollutants in the air to corrode the internal magnesium alloy step by step, eventually resulting in magnesium alloy Corrosion resistance is poor. The two characteristics of difficult plastic deformation and poor corrosion resistance greatly limit the wide application of magnesium alloys in various fields.

As the most widely used non-ferrous metal structural material in industrial applications, aluminum alloy has the characteristics of low density and high specific strength, and can be used as a representative of lightweight structural materials together with magnesium alloy. In addition, the aluminum alloy has a face-centered cubic crystal structure, so it has high plasticity and is easy to process; at the same time, a dense oxide film is easily formed on the surface of the aluminum alloy, which has excellent corrosion resistance. It is precisely because of these characteristics that aluminum alloys can not only make up for the shortcomings of magnesium alloys, but also continue to maintain the lightweight characteristics of structural materials.

Contents of the invention

Aiming at the problems of difficult plastic deformation and corrosion resistance of magnesium alloys, the present invention proposes a magnesium-aluminum double-layer composite cylindrical part. In order to obtain a magnesium-aluminum double-layer composite cylindrical part with good interface bonding strength, a magnesium-aluminum double-layer composite cylindrical part is proposed. Staggered spin forming process for cylindrical parts.

The invention provides a staggered-pitch spinning forming process of a magnesium-aluminum double-layer composite cylindrical part, which includes grinding and cleaning the aluminum alloy outer cylinder and the magnesium alloy inner cylinder obtained by machining, and then performing staggered-pitch spinning. The specific implementation process of distance spinning is as follows:

S1, heating the aluminum alloy outer cylinder and the magnesium alloy inner cylinder to 390°C and keeping it warm for 10 minutes, heating the spinning spindle and the wheel of the three-wheel spinning machine to 200±10°C;

S2, the magnesium alloy inner cylinder is sleeved on the spinning spindle, the aluminum alloy outer cylinder is sleeved outside the magnesium alloy inner cylinder, and the spinning is carried out by using a three-spin wheel staggered forward spinning method, and the spinning The rotational speed of the pressing spindle is 600r/min, the feed speed of the rotary wheel is 0.8mm/r, the feeding direction of the rotary wheel is consistent with the extension direction of plastic deformation of the magnesium alloy inner cylinder and the aluminum alloy outer cylinder, The angle of attack of the spinning wheel is 25°, and the spinning process uses oxyacetylene flame to supplement the heat;

S3, the spinning process is carried out three times in total, without returning to the furnace for heating between each pass. After the three passes, the overall thinning rate of the magnesium-aluminum double-layer composite cylindrical part is 65%, and the thinning rate of each pass is respectively 25%, 25%, 15%.

Further, the aluminum alloy outer cylinder and the magnesium alloy inner cylinder obtained by machining are polished with sandpaper, and cleaned with absolute ethanol after the sandpaper is polished.

Further, when the magnesium alloy inner cylinder is sleeved on the spinning spindle, graphite emulsion lubricant is applied to the spinning spindle.

Furthermore, the machining process of the aluminum alloy outer cylinder and the magnesium alloy inner cylinder is: blanking—rough turning—semi-finishing turning—calibration—finishing turning, and the specific implementation process is as follows:

S1, cutting a cylindrical blank from a magnesium alloy plate and an aluminum alloy plate;

S2, clamp one end of the cylindrical blank, punch holes at the other end, rough turn the inner hole, outer circle and flat end faces at both ends, and leave a preset allowance;

S3, semi-finishing the inner hole, outer circle and flat end faces of the two ends of the semi-finished product after rough turning, and leaving a preset margin;

S4, calibrate the semi-finished product after the semi-finished car;

S5, finish turning the inner hole and the flat end surface of one end of the calibrated semi-finished product, prop up the inner hole, and perform finish turning on the outer circle and the flat end surface of the other end to obtain an aluminum alloy outer cylinder, a magnesium alloy inner cylinder, and an aluminum alloy outer cylinder. The inner hole of the barrel matches the outer circle of the magnesium alloy inner barrel.

Further, the three-rotor spinning machine used in the staggered spinning forming process includes a base, a control cabinet and a spinning chamber arranged on the base, a spinning main shaft arranged in the spinning chamber, a roller bracket, a roller and a tail Top, the motor connected to the spinning main shaft through the coupling, and the wires connecting the control cabinet with the motor and the rotary wheel bracket; the control cabinet is used to control the speed of the motor and the movement of the rotary wheel bracket, and the control cabinet is equipped with a master switch and an indicator A lamp and a display screen; a three-jaw chuck is arranged on the spinning main shaft; the spinning wheel is installed in the spinning chamber through a spinning wheel bracket; the tail top is arranged opposite to the spinning main shaft.

The present invention also provides a magnesium-aluminum double-layer composite cylindrical part, which is made according to the above-mentioned staggered-pitch spinning forming process of the magnesium-aluminum double-layer composite cylindrical part, including an aluminum alloy outer cylinder and an aluminum alloy outer cylinder. Magnesium alloy inner cylinder.

Compared with the prior art, the present invention has the advantages of:

The invention proposes a magnesium-aluminum double-layer composite cylindrical part and its staggered-pitch spinning forming process. The magnesium-aluminum double-layer composite cylindrical part is prepared by adopting the staggered-pitch spinning technology. The composite cylindrical part uses aluminum alloy as the outer layer material , in order to improve the plasticity and corrosion resistance of cylindrical parts, while maintaining its great advantage of light weight. Spinning technology belongs to a near-net-shaping technology. In the process, the surface of the material is subjected to continuous and localized spinning force, so that the material is easy to form. It has been widely used in various fields such as automobiles, aerospace and military industries, and has great potential. The development space, especially the technology of the three-rotor wheel staggered forward rotation method, can make the surface of the cylindrical part have higher precision. The overall thinning rate of the magnesium-aluminum double-layer composite cylindrical part prepared by the staggered pitch spinning forming process provided by the present invention is 65%, and there are no macroscopic defects such as spinning cracks, wrinkles and peeling on the inner and outer surfaces; The microscope and scanning electron microscope observed and analyzed the microstructure of the bonding interface, and found that the two interfaces were well bonded; according to the nanoindentation curve, it can be concluded that the indentation depth of the interface is smaller under the same loading force, which proves that the two are well bonded.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work, wherein:

Fig. 1 is a schematic structural view of a three-wheel spinning machine used in the staggered spinning forming process of a magnesium-aluminum double-layer composite cylindrical part provided in Example 1 of the present invention;

Figure 2 is a schematic diagram of the distribution of the rollers in the three-wheel spinning machine shown in Figure 1;

Fig. 3 is the finished product figure of the magnesium-aluminum double-layer composite cylindrical part provided in the embodiment 3 of the present invention;

Fig. 4 is a scanning electron microscope picture of the magnesium-aluminum double-layer composite cylindrical part shown in Fig. 3;

Fig. 5 is the microstructural diagram of the magnesium-aluminum double-layer composite cylindrical part shown in Fig. 3;

Fig. 6 is the nanoindentation curve of the magnesium-aluminum double-layer composite cylindrical part shown in Fig. 3 .

Labels: 1-base; 2-control cabinet; 3-spinning chamber; 4-spinning spindle; 5-rotary wheel support; 6-rotary wheel; 7-tail top; 8-coupling; 9-motor; -wire; 11-main switch; 12-indicator light; 13-display screen; 14-three-jaw chuck; 101-magnesium-aluminum double-layer composite cylindrical tube; .

Detailed ways

Example 1

This embodiment provides a staggered-pitch spinning forming process for a magnesium-aluminum double-layer composite cylindrical part, which includes grinding and cleaning the aluminum alloy outer cylinder and magnesium alloy inner cylinder obtained by machining, and then performing staggered-pitch spinning, The specific implementation process of staggered spinning is as follows:

S1, heat the aluminum alloy outer cylinder and the magnesium alloy inner cylinder to 390°C and keep it warm for 10 minutes, heat the spinning spindle 4 and the rotary wheel 6 of the three-spinning wheel spinning machine to 200±10°C;

S2, the magnesium alloy inner cylinder is sleeved on the spinning spindle 4, the aluminum alloy outer cylinder is sleeved outside the magnesium alloy inner cylinder, and the spinning is carried out by using the three-wheel staggered forward rotation method, and the rotation speed of the spinning spindle 4 is 600r/min , the feed speed of the rotary wheel 6 is 0.8mm/r, the feeding direction of the rotary wheel 6 is consistent with the extension direction of the plastic deformation of the magnesium alloy inner cylinder and the aluminum alloy outer cylinder, the attack angle of the rotary wheel 6 is 25°, and the spinning The process adopts oxyacetylene flame for supplementary heat;

S3, the spinning process is carried out three times in total, without returning to the furnace for heating between each pass. After the three passes, the overall thinning rate of the magnesium-aluminum double-layer composite cylindrical part is 65%, and the thinning rate of each pass is respectively 25%, 25%, 15%.

Further, the aluminum alloy outer cylinder and the magnesium alloy inner cylinder obtained by machining are polished with sandpaper, and cleaned with absolute ethanol after the sandpaper is polished.

Further, when the magnesium alloy inner cylinder is sleeved on the spinning spindle 4, graphite emulsion lubricant is applied on the spinning spindle 4.

Furthermore, the machining process of the aluminum alloy outer cylinder and the magnesium alloy inner cylinder is: blanking—rough turning—semi-finishing turning—calibration—finishing turning, and the specific implementation process is as follows:

S1, cutting a cylindrical blank from a magnesium alloy plate and an aluminum alloy plate;

S2, clamp one end of the cylindrical blank, punch holes at the other end, rough turn the inner hole, outer circle and flat end faces at both ends, and leave a preset allowance;

S3, semi-finishing the inner hole, outer circle and flat end faces of the two ends of the semi-finished product after rough turning, and leaving a preset margin;

S4, calibrate the semi-finished product after the semi-finished car;

S5, finish turning the inner hole and the flat end surface of one end of the calibrated semi-finished product, prop up the inner hole, and perform finish turning on the outer circle and the flat end surface of the other end to obtain an aluminum alloy outer cylinder, a magnesium alloy inner cylinder, and an aluminum alloy outer cylinder. The inner hole of the barrel matches the outer circle of the magnesium alloy inner barrel.

Further, as shown in Figure 1 and Figure 2, the three-rotor spinning machine used in the staggered spinning forming process includes a base 1, a control cabinet 2 and a spinning chamber 3 arranged on the base 1, and a spinning chamber 3, the spinning main shaft 4, the rotary wheel bracket 5, the rotary wheel 6 and the tail top 7, the motor 9 connected to the spinning main shaft 4 through the coupling 8, and the control cabinet 2 connected to the motor 9 and the rotary wheel bracket 5 The wire 10; the control cabinet 2 is used to control the speed of the motor 9 and the movement of the rotary wheel bracket 5, the control cabinet 2 is provided with a main switch 11, an indicator light 12 and a display screen 13; the spinning spindle 4 is provided with a three-jaw chuck 14 The rotary wheel 6 is installed in the spinning chamber 3 through the rotary wheel bracket 5; the tail top 7 is set opposite to the spinning spindle 4. After the magnesium-aluminum double-layer composite cylindrical tube blank 101 is set on the spinning spindle 4, the magnesium-aluminum double-layer composite cylindrical tube blank 101 is clamped and fixed with the tail top 7, and the main switch 11 is turned on. According to the preset parameters, the motor 9 rotates, the rotary wheel support 5 moves, and the magnesium-aluminum double-layer composite cylindrical tube blank 101 is formed by the spinning of the rotary wheel 6 into the formed area 102 of the magnesium-aluminum double-layer composite cylindrical part. .

Example 2

This embodiment provides a magnesium-aluminum double-layer composite cylindrical part, which is made according to the staggered spinning process of the magnesium-aluminum double-layer composite cylindrical part described in Embodiment 1, including an aluminum alloy outer cylinder and an aluminum alloy outer cylinder. Magnesium alloy inner barrel inside the barrel.

The composite cylindrical part uses aluminum alloy as the outer layer material to improve the corrosion resistance of the cylindrical part while maintaining its great advantage of light weight; the overall thinning rate is 65%; there are no spinning cracks and wrinkles on the inner and outer surfaces And macroscopic defects such as peeling appear; through the observation and analysis of the microstructure of the bonding interface with a metallographic microscope and a scanning electron microscope, it is found that the two interfaces are well bonded; according to the nano-indentation curve, it can be concluded that the interface under the same loading force The indentation depth is smaller, which proves that the two are well combined.

Example 3

This embodiment takes AZ31 magnesium alloy plate and 2024Al aluminum alloy plate as examples to further illustrate the staggered pitch spinning process of the magnesium-aluminum double-layer composite cylindrical part described in embodiment 1 and the magnesium-aluminum double-layer described in embodiment 2. Composite barrel. The size of the AZ31 magnesium alloy plate is 300mm×300mm×25mm, and the size of the 024Al aluminum alloy plate is 300mm×300mm×30mm.

The staggered spinning forming process of magnesium-aluminum double-layer composite cylindrical parts is as follows.

(1) Machining

The machining process of aluminum alloy outer cylinder and magnesium alloy inner cylinder is: blanking - rough turning - semi-finishing turning - calibration - finishing turning, the specific implementation process is:

S1, cutting cylindrical blanks with a wire cutting machine on the magnesium alloy plate and the aluminum alloy plate;

S2, use the three-jaw chuck 14 to clamp one end of the cylindrical blank, punch holes at the other end, carry out rough turning on the inner hole, the outer circle and the flat end faces of both ends, and leave a margin of 2mm;

S3, semi-finishing the inner hole, outer circle and flat end faces of both ends of the semi-finished product after rough turning, and leave a margin of 0.2mm;

S4, calibrate the semi-finished product after semi-finishing, and adjust the three-jaw chuck 14 to obtain an appropriate clamping force after calibration;

S5, finish turning the inner hole of the calibrated semi-finished product and the flat end surface at one end, use the three-jaw chuck 14 to prop up the inner hole, and perform finish turning on the outer circle and the flat end surface at the other end.

After machining, the roughness of the inner and outer surfaces of the aluminum alloy outer cylinder and the magnesium alloy inner cylinder and the flat end surface is Ra0.08-0.16µm. The diameter of the inner hole of the aluminum alloy outer cylinder is 28mm, the length of the inner hole is 20mm, the diameter of the outer circle is 32mm, and the length of the outer circle is 22mm; The inner hole of the alloy outer cylinder fits.

(2) Staggered pitch spinning

First, polish the machined aluminum alloy outer cylinder and magnesium alloy inner cylinder with 400# sandpaper to remove oil stains and broken surface oxide films on the surface of the cylindrical parts; Clean the inner and outer surfaces and the flat end surface to avoid the formation of dense oxide film in a short time.

The specific implementation process of staggered spinning is as follows:

S1, heat the aluminum alloy outer cylinder and the magnesium alloy inner cylinder to 390°C and keep it warm for 10 minutes, heat the spinning spindle 4 and the rotary wheel 6 of the three-spinning wheel spinning machine to 200±10°C;

S2, apply graphite emulsion lubricant on the spinning spindle 4 to disassemble the workpiece, set the magnesium alloy inner cylinder on the spinning spindle 4, set the aluminum alloy outer cylinder outside the magnesium alloy inner cylinder, and adopt the three-rotation wheel staggered pitch Spinning is carried out by the positive spinning method, the rotating speed of the spinning spindle 4 is 600r/min, the feed speed of the rotary wheel 6 is 0.8mm/r, and the feeding direction of the rotary wheel 6 is plastically deformed with the magnesium alloy inner cylinder and the aluminum alloy outer cylinder The extension direction is the same, the angle of attack of the rotary wheel 6 is 25°, and the spinning process uses oxyacetylene flame to supplement the heat;

S3, the spinning process is carried out three times in total, without returning to the furnace for heating between each pass. After the three passes, the overall thinning rate of the magnesium-aluminum double-layer composite cylindrical part is 65%, and the thinning rate of each pass is respectively 25%, 25%, 15%.

(3) Grinding and cleaning

Polish the inner and outer surfaces and the flat end surface of the magnesium-aluminum double-layer composite cylindrical part processed by spinning with 600# sandpaper to achieve the effect of removing oil stains; then clean the polished composite cylindrical part with absolute ethanol to maintain clean.

(4) Detection, analysis, characterization

The finished product diagram of the composite tubular part macroscopically, as shown in Figure 3;

Observe the interface structure of the composite cylindrical part with a scanning electron microscope, as shown in Figure 4;

Use a metallographic microscope to observe the interface bonding of the composite cylindrical part, as shown in Figure 5;

The interface performance of the composite cylindrical part was analyzed with a nano-indentation instrument, as shown in Figure 6;

Conclusion: The overall thinning rate of the magnesium-aluminum double-layer composite cylindrical parts processed by the three-spin wheel staggered forward rotation method is 65%, and there are no macroscopic defects such as spinning cracks, wrinkles and peeling on the inner and outer surfaces. By observing and analyzing the microstructure of the bonding interface with a scanning electron microscope and a metallographic microscope, it is found that the interface of the two is well bonded. According to the nanoindentation curve, it can be concluded that the indentation depth of the interface is smaller under the same loading force, which proves that the two are well combined.

(5) Storage

The magnesium-aluminum double-layer composite cylindrical parts processed by the three-rotation wheel staggered forward rotation method are packaged with soft materials and stored in a clean and dry environment. They must be protected from moisture, sun, and acid, alkali, and salt erosion. The storage temperature is 20°C. The relative humidity is ≤10%.

The above are only examples of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the description of the present invention, or directly or indirectly used in other related technical fields, is the same. included in the scope of patent protection of the present invention.

Claims (6)

1. a kind of stepped spinning moulding process of magnalium two-layer compound cylindrical member, it is characterised in that：Including being obtained to mechanical processing Aluminium alloy outer barrel and after magnesium alloy inner cylinder polished and cleaned, carry out stepped spinning processing, stepped spinning processing is specific real The process of applying is：

S1 heats the aluminium alloy outer barrel and magnesium alloy inner cylinder to 390 DEG C and keeps the temperature 10min, heats the rotation of three spinning-roller spinning machines Press main shaft（4）And spinning roller（6）To 200 ± 10 DEG C；

S2, the magnesium alloy inner cylinder are sheathed on the spinning main shaft（4）On, the aluminium alloy outer sleeve is set in the magnesium alloy Cylinder is outer, and spinning, the spinning main shaft are carried out away from dextrorotation method using three spinning roller mistakes（4）Rotating speed be 600r/min, the spinning roller（6） Feed speed be 0.8mm/r, the spinning roller（6）Direction of feed and the magnesium alloy inner cylinder and aluminium alloy outer barrel plasticity occurs It is consistent to deform extending direction, the spinning roller（6）The angle of attack be 25 °, spinning process using oxyacetylene torch carry out concurrent heating；

S3, spinning process carry out three passages altogether, do not melt down heating between every time, magnalium two-layer compound cylindrical member after three passages Overall reduction be 65%, every time reduction is respectively 25%, 25%, 15%.

2. the stepped spinning moulding process of magnalium two-layer compound cylindrical member according to claim 1, which is characterized in that machine It is polished using sand paper when the aluminium alloy outer barrel and magnesium alloy inner cylinder that tool is processed are polished, absolute ethyl alcohol is used after sand paper polishing Cleaning.

3. the stepped spinning moulding process of magnalium two-layer compound cylindrical member according to claim 1, which is characterized in that by institute It states magnesium alloy inner cylinder and is sheathed on the spinning main shaft（4）When upper, in the spinning main shaft（4）Upper smearing aquadag lubricant.

4. according to the stepped spinning moulding process of claim 1-3 any one of them magnalium two-layer compound cylindrical members, feature It is, the mechanical processing process of the aluminium alloy outer barrel and magnesium alloy inner cylinder is：Blanking-is rough turn-half smart car-calibration-essence The process of vehicle, specific implementation is：

S1 cuts cylinder blank on magnesium alloy plate and aluminium alloy plate；

S2 clamps one end of the cylinder blank, is punched in the other end, to endoporus, outer circle and the planar end surface at both ends It carries out rough turn, and reserves default surplus；

S3 carries out half smart car to the endoporus of the semi-finished product after rough turn, outer circle and the planar end surface at both ends, and reserves default surplus；

S4, the semi-finished product after double of smart car are calibrated；

The planar end surface of S5, endoporus and one end to the semi-finished product after calibration carry out smart car, prop up endoporus, to foreign round and another The planar end surface at end carries out smart car, obtains the aluminium alloy outer barrel and magnesium alloy inner cylinder, the endoporus of the aluminium alloy outer barrel with it is described The outer circle of magnesium alloy inner cylinder matches.

5. the stepped spinning moulding process of magnalium two-layer compound cylindrical member according to claim 4, which is characterized in that it is wrong away from Three spinning-roller spinning machines used in flow forming and molding process include pedestal（1）, be arranged in the pedestal（1）On switch board（2）And rotation Pressure chamber（3）, be arranged in the spinning room（3）Interior spinning main shaft（4）, spinning roller holder（5）, spinning roller（6）With tail top（7）, pass through Shaft coupling（8）With the spinning main shaft（4）The motor of connection（9）And the connection switch board（2）With motor（9）And spinning roller Holder（5）Conducting wire（10）；

The switch board（2）For controlling the motor（9）Rotating speed and the spinning roller holder（5）Movement, the switch board （2）On be provided with master switch（11）, indicator light（12）And display screen（13）；

The spinning main shaft（4）On be provided with scroll chuck（14）；

The spinning roller（6）Pass through the spinning roller holder（5）Mounted on the spinning room（3）It is interior；

The tail top（7）With the spinning main shaft（4）It is oppositely arranged.

6. a kind of magnalium two-layer compound cylindrical member, which is characterized in that the magnalium two-layer compound tubular according to claim 1-5 The stepped spinning moulding process of part is made, including in aluminium alloy outer barrel and the magnesium alloy that is arranged in the aluminium alloy outer barrel Cylinder.