High-efficiency processing equipment and processing method for magnesium alloy

Abstract

The present invention discloses an efficient processing equipment for magnesium alloy and a processing method thereof, comprising a pair of forming dies, both of which are provided with two pairs of die fastening bolt openings, the two forming dies being fixedly connected via the two pairs of die fastening bolt openings, a forming channel being provided in the forming dies, the forming channel comprising, from top to bottom, a feed port, an asymmetric shear coupling expansion deformation zone, an expansion deformation zone, an asymmetric shear coupling diameter reduction deformation zone, an extrusion ratio deformation zone and a discharge port, a pressure head being provided at the top of the feed port, the outer edge of the pressure head being in contact with the inner wall of the feed port; by using the equipment of the present invention to process magnesium alloy, shear expansion, shear diameter extrusion deformation of the material can be simultaneously achieved after a single-pass processing, thereby reducing processing costs and greatly improving processing efficiency; at the same time, the processing method of the present invention can accumulate higher equivalent strain, better induce dynamic recrystallization, and ultimately improve the performance of the magnesium alloy.

Description

Technical Field

[0001] The present invention relates to the technical field of alloy processing, and more particularly to a high-efficiency processing device for magnesium alloy and a processing method thereof. Background Art

[0002] Magnesium alloy is the lightest metal composite material currently used in industrial applications. It has the advantages of high specific strength, high specific modulus, high damping, excellent electromagnetic shielding and cutting processing performance, easy recycling and abundant resources. The development of manufacturing technology for high-performance magnesium alloys is of great significance to the expansion and application of 3C electronic products, aerospace, automotive parts and military industries.

[0003] Large plastic extrusion deformation technology is the process with the most significant optimization effect at present. The most advanced technologies include: rectangular vortex extrusion, alternating extrusion, asymmetric extrusion chamber cyclic expansion extrusion, static pressure tube cyclic expansion extrusion, turning bearing extrusion, etc.

[0004] However, existing extrusion molding methods generally have the disadvantage of requiring repeated multiple extrusion passes, resulting in low processing efficiency, time-consuming processing, and high processing costs. Summary of the Invention

[0005] The present invention provides a high-efficiency processing device and a processing method for magnesium alloys, so as to solve the problems in the prior art of extrusion molding methods that multiple extrusions are required repeatedly, resulting in low processing efficiency, time-consuming processing and high processing costs.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] It includes a pair of forming molds, each of which is provided with two pairs of mold fastening bolt openings, and the two forming molds are fixedly connected by the two pairs of mold fastening bolt openings. A forming channel is provided in the forming mold, and the forming channel includes a feed port, an asymmetric shear coupling expansion deformation zone, an expansion deformation zone, an asymmetric shear coupling diameter reduction deformation zone, an extrusion ratio deformation zone and a discharge port from top to bottom. A discharge channel is provided at the bottom end of the discharge port, and the discharge channel is divided into two sections, including a first section directly connected to the discharge port and a second section connected subsequently. The first section of the discharge channel is equal to the inner diameter of the discharge port, and the length of the first section of the discharge channel is 3mm-7mm. The ratio of the inner diameter of the second section of the discharge channel to the inner diameter of the discharge port is 10:8. A pressure head is provided at the top of the feed port, and the outer edge of the pressure head is in contact with the inner wall of the feed port.

[0008] Preferably, the top diameter size of the asymmetric shear coupling expansion deformation zone is D1, the bottom diameter size of the asymmetric shear coupling expansion deformation zone is D2, the longitudinal span of the asymmetric shear coupling expansion deformation zone is L1, the value of D1 is 20-40 mm, the value of D2 is 30-52 mm, the value of L1 is 5-8 mm, and the value of D2 is at least 15% greater than the value of D1.

[0009] Preferably, the diameters of the top and bottom of the expansion deformation zone are both D2, the longitudinal span of the expansion deformation zone is L2, the value of L2 is 3-5 mm, and the value of L1 is greater than L2.

[0010] Preferably, the top diameter of the asymmetric shear coupling diameter reducing deformation zone is D2, and the longitudinal span of the asymmetric shear coupling diameter reducing deformation zone is L1.

[0011] Preferably, the bottom diameter of the extrusion ratio deformation zone is D3, the top diameter of the extrusion ratio deformation zone is equal to the bottom diameter of the asymmetric shear coupling diameter reduction deformation zone, the longitudinal span of the extrusion ratio deformation zone is L3, the D3 value range is 6-10mm, the L3 value range is 8-13mm, and the offset distance d between the bottom axis of the extrusion ratio deformation zone and the top axis of the asymmetric shear coupling expansion deformation zone is in the range of 3-5mm.

[0012] Preferably, the feed port and the discharge port are both cylindrical, the angles between the feed port and the two sides of the asymmetric shear coupling expansion deformation zone are ψ1 and ψ2 respectively, and the transition area between the two asymmetric curved surfaces is chamfered.

[0013] Preferably, the angles between the inclined surfaces on both sides of the asymmetric shear coupling diameter reducing deformation zone and the vertical direction are ψ1 and ψ2 respectively, and the side of the asymmetric shear coupling diameter reducing deformation zone with an inclined surface angle of ψ1 and the side of the asymmetric shear coupling expansion deformation zone with an inclined surface angle of ψ1 are staggered.

[0014] Preferably, a method for using an efficient processing device for magnesium alloys is characterized by comprising the following steps:

[0015] S1: Assemble the two forming dies through the die fastening bolt ports and place the raw material to be extruded into the feed port;

[0016] S2: Predict the length and volume of the processed bar, select a suitable length of the pressing head, adjust the pressing head to be just above the feed port, and then move the pressing head downward in the vertical direction to squeeze the raw material to be extruded;

[0017] S3: Under the influence of the press work, the ram pushes the material downward, and the entire extrusion process needs to maintain a uniform extrusion speed.

[0018] S4: When the bottom end of the ram is 2-4 mm away from the top plane of the asymmetric shear coupling expansion deformation zone, the top end of the die contacts the ram limiting structure, ending the extrusion process. After the extruded raw material is completely discharged from the discharge channel at the bottom of the discharge port, the two forming dies are separated and the ram is reset, completing one magnesium alloy processing.

[0019] The principle and beneficial effects of this technical solution:

[0020] (1) When the magnesium alloy is processed by the present invention, the material is pressed downward. The material will first undergo coupled expansion in the asymmetric shear coupling expansion deformation zone, the expansion deformation zone, and the asymmetric shear coupling diameter reduction deformation zone. After the extrusion expansion fills the above-mentioned zones, the material continues to be extruded downward after the expansion is completed. Due to the flow velocity difference formed by the internal structure of the mold, the shear deformation is completed, and the grains of the magnesium alloy are effectively refined through extrusion and shear plastic forming. After entering the extrusion ratio deformation zone, the magnesium alloy grains are further refined to form a second phase. Through shear expansion and shear diameter extrusion deformation, a higher equivalent strain can be accumulated, which can better induce dynamic recrystallization and ultimately improve the performance of the magnesium alloy.

[0021] (2) Taking AZ31 magnesium alloy as an example, after single-pass processing using a spatially symmetrical shear expansion rotary extrusion integrated forming die, the TUS (ultimate tensile strength) increased by 12-20%, while the elongation increased to 16-18%. This has reached the level of first-class multi-pass extrusion dies at home and abroad; compared with other high-performance extrusion processes on the market (more than 90% of which are multi-pass extrusion), the processing efficiency has increased by at least 4 times. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the structure of the mold in the present invention;

[0023] Figure 2 Schematic diagram of the distance dimensions of the forming area in the present invention;

[0024] Figure 3 Schematic diagram of the angle dimensions of the processing area in the present invention;

[0025] The figure marks in the drawings of the specification include: 1. mold fastening bolt port; 2. forming mold; 3. asymmetric shear coupling diameter reduction deformation zone; 4. discharge port; 5. feed port; 6. asymmetric shear coupling expansion deformation zone; 7. expansion deformation zone; 8. extrusion ratio deformation zone. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments: Example

[0027] like Figure 1As shown, it includes a pair of forming molds 2, and two pairs of mold fastening bolt openings 1 are opened on the two forming molds 2. The two forming molds are fixedly connected by the two pairs of mold fastening bolt openings 1. A forming channel is opened in the forming mold 2, and the forming channel includes a feed port 5, an asymmetric shear coupling expansion deformation zone 6, an expansion deformation zone 7, an asymmetric shear coupling diameter reduction deformation zone 3, an extrusion ratio deformation zone 8 and a discharge port 4 from top to bottom. A discharge channel is provided at the bottom end of the discharge port 4, and the discharge channel is divided into two sections, including a first section directly connected to the discharge port and a second section connected subsequently. The inner diameter of the first section of the discharge channel is equal to that of the discharge port, and the length of the first section of the discharge channel is 3mm-7mm. The ratio of the inner diameter of the second section of the discharge channel to the inner diameter of the discharge port 4 is 10:8. A pressure head is provided at the top of the feed port 5, and the outer edge of the pressure head is in contact with the inner wall of the feed port 5.

[0028] The discharge channel and the discharge port maintain the same diameter at a certain distance, which can reduce the risk of bending and deviation of the discharge; the discharge channel is designed to be larger than the discharge port, which can reduce the friction of the discharge and the internal stress of the discharge, thereby facilitating smooth discharge.

[0029] like Figure 1 and Figure 2 As shown, the top diameter size of the asymmetric shear coupling expansion deformation zone 6 is D1, the bottom diameter size of the asymmetric shear coupling expansion deformation zone 6 is D2, the longitudinal span of the asymmetric shear coupling expansion deformation zone 6 is L1, D1 is 20-40 mm, D2 is 30-52 mm, L1 is 5-8 mm, and D2 is at least 15% greater than D1.

[0030] like Figure 1 and Figure 2 As shown, the diameters of the top and bottom of the expansion and deformation zone 7 are both D2, the longitudinal span of the expansion and deformation zone 7 is L2, the value of L2 is 3-5 mm, and the value of L1 is greater than L2.

[0031] like Figure 1 and Figure 2 As shown, the top diameter of the asymmetric shear coupling diameter reducing deformation zone 3 is D2, and the longitudinal span of the asymmetric shear coupling diameter reducing deformation zone 3 is L1.

[0032] like Figure 1 and Figure 2 As shown, the bottom diameter of the extrusion ratio deformation zone 8 is D3, the top diameter of the extrusion ratio deformation zone 8 is equal to the bottom diameter of the asymmetric shear coupling diameter reduction deformation zone 3, the longitudinal span of the extrusion ratio deformation zone 8 is L3, the D3 value range is 6-10mm, the L3 value range is 8-13mm, and the offset distance d between the bottom axis of the extrusion ratio deformation zone 8 and the top axis of the asymmetric shear coupling expansion deformation zone 6 is in the range of 3-5mm.

[0033] like Figure 1 and Figure 3 As shown, the feed port 5 and the discharge port 4 are both cylindrical, and the angles between the feed port 5 and the two sides of the asymmetric shear coupling expansion deformation zone 6 are ψ1 and ψ2 respectively, and the transition area between the two asymmetric surfaces is chamfered.

[0034] like Figure 1 and Figure 3 As shown, the angles between the inclined surfaces on both sides of the asymmetric shear coupling diameter reducing deformation zone 3 and the vertical direction are ψ1 and ψ2 respectively, and the side of the asymmetric shear coupling diameter reducing deformation zone 3 with the inclined surface angle ψ1 and the side of the asymmetric shear coupling expansion deformation zone 6 with the inclined surface angle ψ1 are staggered.

[0035] When magnesium alloy is processed by the present invention, the material is pressed downward. The material will first contact the right side of the asymmetric shear coupling diameter-reducing deformation zone 3 before the asymmetric shear coupling expansion deformation zone 6, the expansion deformation zone 7, and the asymmetric shear coupling diameter-reducing deformation zone 3, and bend horizontally in one direction due to the shape of the mold until the entire asymmetric shear coupling diameter-reducing deformation zone 3 is filled. As the downward pressure continues, since the extrusion ratio deformation zone 8 in the lower area is a shear diameter structure, under the influence of reaction force and friction, the material will first reversely expand toward the asymmetric shear coupling expansion deformation zone 6 and the expansion deformation zone 7, and then fill the three areas of the asymmetric shear coupling expansion deformation zone 6, the expansion deformation zone 7, and the asymmetric shear coupling diameter-reducing deformation zone 3 through extrusion expansion. After the expansion is completed, the material continues to be extruded downward. Due to the internal structure of the mold and the eccentric distance between the feed port 5 and the asymmetric shear coupling diameter-reducing deformation zone 3 and the extrusion ratio deformation zone 8, a flow velocity difference is formed, and shear deformation is completed in the above three areas.

[0036] Magnesium alloy grains undergo plastic deformation through expansion and shear deformation, effectively refining the grains. They then enter the shear-to-radial extrusion ratio deformation zone, further refining the magnesium alloy grains and forming a secondary phase. Shear-to-radial extrusion deformation accumulates a higher equivalent strain, better inducing dynamic recrystallization and ultimately improving the performance of magnesium alloys.

[0037] The specific usage and function of this embodiment are as follows:

[0038] S1: Assemble the two forming dies 2 through the die fastening bolt port 1, and place the raw material to be extruded into the feed port 5;

[0039] S2: Predict the length and volume of the processed bar material, select a pressing head of appropriate length, adjust the pressing head to be just above the feed port 5, and then move the pressing head downward in the vertical direction to squeeze the material to be extruded downward;

[0040] S3: Under the influence of the press work, the ram pushes the material downward, and the entire extrusion process needs to maintain a uniform extrusion speed.

[0041] S4: When the bottom end of the ram is 2-4 mm away from the top plane of the asymmetric shear coupling expansion deformation zone 6, the top end of the mold contacts the ram limiting structure, ending the extrusion process. After the extruded raw material is completely discharged from the discharge channel at the bottom end of the discharge port 4 to the forming mold 2, the two forming molds 2 are separated and the ram is reset, completing one magnesium alloy processing.

[0042] The above is only an embodiment of the present invention, and the common knowledge such as the specific technical solutions and / or characteristics in the solution are not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the description can be used to interpret the content of the claims.

Claims

1. An efficient processing equipment for magnesium alloys, characterized by: The invention comprises a pair of forming dies (2), two pairs of die fastening bolt openings (1) are provided on each of the two forming dies (2), the two forming dies are fixedly connected by the two pairs of die fastening bolt openings (1), a forming channel is provided in the forming dies (2), the forming channel comprises a feed port (5), an asymmetric shear coupling expansion deformation zone (6), an expansion deformation zone (7), an asymmetric shear coupling diameter reduction deformation zone (3), an extrusion ratio deformation zone (8) and a discharge port (4) from top to bottom, a discharge channel is provided at the bottom end of the discharge port (4), the discharge channel is divided into two sections, including a first section directly connected to the discharge port and a second section connected subsequently, the first section of the discharge channel has the same inner diameter as the discharge port, the length of the first section of the discharge channel is 3mm-7mm, the ratio of the inner diameter of the second section of the discharge channel to the inner diameter of the discharge port (4) is 10:8, a pressure head is provided at the top end of the feed port (5), the outer edge of the pressure head is in contact with the inner wall of the feed port (5); When magnesium alloy is processed, the material is pressed down. The material will first contact the right side of the asymmetric shear coupling diameter reduction deformation zone (3) before the asymmetric shear coupling expansion deformation zone (6) and the expansion deformation zone (7), and bend horizontally in one direction due to the shape of the mold until the entire asymmetric shear coupling diameter reduction deformation zone (3) is filled. As the downward pressure continues, since the extrusion ratio deformation zone (8) in the lower area is a shear diameter structure, under the influence of the reaction force and friction force, the material will first reverse to the asymmetric shear coupling expansion deformation zone (6) and the expansion deformation zone (7) for coupled expansion. After the extrusion expansion, the three areas of the asymmetric shear coupling expansion deformation zone (6), the expansion deformation zone (7), and the asymmetric shear coupling diameter reduction deformation zone (3) are filled. After the expansion is completed, the material continues to be extruded downward. Due to the internal structure of the mold and the eccentric distance between the feed port (5) and the asymmetric shear coupling diameter reduction deformation zone (3) and the extrusion ratio deformation zone (8), a flow rate difference is formed, and shear deformation is completed in the above three areas.

2. The high-efficiency processing equipment for magnesium alloy according to claim 1, characterized in that: The top diameter of the asymmetric shear coupling expansion deformation zone (6) is D1, the bottom diameter of the asymmetric shear coupling expansion deformation zone (6) is D2, the longitudinal span of the asymmetric shear coupling expansion deformation zone (6) is L1, the value of D1 is 20-40 mm, the value of D2 is 30-52 mm, the value of L1 is 5-8 mm, and the value of D2 is at least 15% greater than the value of D1.

3. The high-efficiency processing equipment for magnesium alloy according to claim 2, characterized in that: The diameters of the top and bottom of the expansion deformation zone (7) are both D2, the longitudinal span of the expansion deformation zone (7) is L2, the value of L2 is 3-5 mm, and the value of L1 is greater than L2.

4. The high-efficiency processing equipment for magnesium alloy according to claim 3, characterized in that: The top diameter of the asymmetric shear coupling diameter-reducing deformation zone (3) is D2, and the longitudinal span of the asymmetric shear coupling diameter-reducing deformation zone (3) is L1.

5. The high-efficiency processing equipment for magnesium alloy according to claim 4, characterized in that: The bottom diameter of the extrusion ratio deformation zone (8) is D3, the top diameter of the extrusion ratio deformation zone (8) is equal to the bottom diameter of the asymmetric shear coupling diameter reduction deformation zone (3), the longitudinal span of the extrusion ratio deformation zone (8) is L3, the value range of D3 is 6-10mm, the value range of L3 is 8-13mm, and the offset distance d between the bottom axis of the extrusion ratio deformation zone (8) and the top axis of the asymmetric shear coupling expansion deformation zone (6) is in the range of 3-5mm.

6. The high-efficiency processing equipment for magnesium alloy according to claim 5, characterized in that: The feed port (5) and the discharge port (4) are both cylindrical, and the angles between the feed port (5) and the two sides of the asymmetric shear coupling expansion deformation zone (6) are ψ1 and ψ2 respectively, and the transition area between the two asymmetric curved surfaces is chamfered.

7. The high-efficiency processing equipment for magnesium alloy according to claim 6, characterized in that: The angles between the inclined surfaces on both sides of the asymmetric shear coupling diameter reducing deformation zone (3) and the vertical direction are ψ1 and ψ2 respectively, and the side of the asymmetric shear coupling diameter reducing deformation zone (3) with the inclined surface having the angle ψ1 and the side of the asymmetric shear coupling expansion deformation zone (6) with the inclined surface having the angle ψ1 are staggered.

8. A method for using the high-efficiency processing equipment for magnesium alloys according to claim 7, characterized in that: The following steps are involved: S1: Assemble the two forming dies (2) through the die fastening bolt openings (1), and place the raw material to be extruded into the feed port (5); S2: Predict the length and volume of the processed bar material, select a suitable length of the pressing head, adjust the pressing head to be just above the feed port (5), and then move the pressing head downward in the vertical direction so that the pressing head presses the material to be extruded downward; S3: The ram pushes the material downward under the influence of the press work, and the entire extrusion process needs to maintain a uniform extrusion speed; S4: When the bottom end of the ram is 2-4 mm away from the top plane of the asymmetric shear coupling expansion deformation zone (6), the top end of the die contacts the ram limiting structure, ending the extrusion process. After the extruded raw material is completely discharged from the forming die (2) through the discharge channel at the bottom end of the discharge port (4), the two forming dies (2) are separated and the ram is reset, thus completing one magnesium alloy processing.

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