CN110695336A

CN110695336A - Semisolid magnesium alloy gradient extrusion combined die

Info

Publication number: CN110695336A
Application number: CN201910993511.0A
Authority: CN
Inventors: 贾伟涛; 马立峰; 雷军义; 邹景锋
Original assignee: Taiyuan University of Science and Technology
Current assignee: Taiyuan University of Science and Technology
Priority date: 2019-10-18
Filing date: 2019-10-18
Publication date: 2020-01-17
Anticipated expiration: 2039-10-18
Also published as: CN110695336B

Abstract

The invention provides a semi-solid magnesium alloy gradient extrusion combined die, wherein the left side of a supporting plate is fixedly connected with a casting and rolling machine frame through a bolt, the right side of the supporting plate is connected with a temperature control chamber through a bolt, the inside of the temperature control chamber is connected with a shunting chamber, a male die and a female die in an interference fit manner, the supporting plate is connected with the shunting chamber through a bolt, the right side of the shunting chamber is connected with the male die and the female die in a clearance fit manner, the right end of the temperature control chamber is connected with a support through a bolt, the support is connected with the; namely, the mold core is in interference fit with the core hole, the solution is shunted by the shunt bridge to enter the shunt hole, then enters the welding chamber and finally flows out through the core hole, and backward spiral cooling liquid is distributed around the male mold and the female mold, so that the solid phase rate of the solution is controlled. The invention effectively improves the texture distribution, weakens the anisotropy, improves the plastic forming capability of the product and saves the energy; has the advantages of high productivity, good quality, strong flexibility and stable production and positive effects.

Description

Semisolid magnesium alloy gradient extrusion combined die

Technical Field

The invention relates to the technical field of magnesium alloy processing, in particular to a semisolid magnesium alloy gradient extrusion combined die.

Background

The magnesium alloy has the advantages of light weight, high specific strength, good heat dissipation and shock absorption, good precision formability, recoverability and the like, and is an ideal choice for metal structure materials of aerospace, rail transit, automobiles, portable military industry and civil products. But the further development and application of the magnesium alloy are hindered by the poor plasticity, easy cracking, quick heat dissipation, low ductility and poor plastic processing capability of the magnesium and the magnesium alloy. The extrusion processing is used as an important process for producing the magnesium alloy section, and the magnesium alloy section has the advantages of compact product, strong performance and the like, so that the magnesium alloy section is widely applied to the production of magnesium alloys.

At present, most of magnesium alloy sections adopt a large plastic deformation technology to achieve the purposes of grain refinement and texture regulation. The large plastic deformation technology comprises the process methods of equal channel extrusion, continuous extrusion, variable channel extrusion, bidirectional extrusion, asymmetric extrusion, forward extrusion, equal channel angular extrusion, continuous semi-solid extrusion forming and the like. Wherein, the traditional extrusion forming process has the defects of obvious product anisotropy, difficult control of basal plane texture, poor mechanical property and complex process; the novel extrusion forming process has the advantages of strong plastic deformation, large shearing force, grain refinement, good structure performance and the like, but has the defects of discontinuous process production, low efficiency, high cost and the like.

In the plastic forming process of the magnesium alloy pipe, crystal grain refinement and texture regulation are carried out, so that the texture distribution is improved, the anisotropy is weakened, the plastic forming capability of a product is improved, and the mechanical property, the subsequent forming property and the precision of the magnesium alloy pipe are improved, thereby becoming the technical key of a novel extrusion forming process. Therefore, a novel processing and forming technology with strong controllability, uniform and excellent preparation, stability, reliability and good product performance is urgently needed to be developed, and the comprehensive performance of the magnesium alloy pipe is improved.

Disclosure of Invention

The invention aims to provide a semi-solid magnesium alloy gradient extrusion combined die which can effectively solve the technical problems of poor bearing capacity, outstanding anisotropy, limited specification of the traditional magnesium alloy welded pipe produced by extrusion, long flow, poor flexibility, low productivity, high production cost and the like of the conventional rolling production process.

In order to achieve the purpose, the invention adopts the technical scheme that: the utility model provides a half solid-state magnesium alloy gradient extrusion assembling die, its structure includes: the device comprises a supporting plate, a shunting chamber, a temperature control chamber, a male die, a female die, a core rod, a spiral water through hole, a support, a base, a shunting bridge, a mold core, shunting holes, a welding chamber and core holes; the left side of the supporting plate is fixedly connected with a casting and rolling machine frame through a bolt, the right side of the supporting plate is connected with a temperature control chamber through a bolt, the interior of the temperature control chamber is connected with a shunting chamber, a male die and a female die in an interference fit mode, the supporting plate is connected with the shunting chamber through a bolt, the right side of the shunting chamber is connected with the male die and the female die in a clearance fit mode, the right end of the temperature control chamber is connected with a support through a bolt, the support is connected with the female die through; namely, the mold core is in interference fit with the core hole, the outer side of the core rod and the inner sides of the punch and the die form a shunting area D1 with equal intervals, a shearing area D2 with different intervals and an extrusion cavity sizing area D3 with equal intervals; the first section is a shunting area formed by gradually reducing the inner diameter from left to right, the second section is a vertically asymmetric shearing area, and the third section is a vertically symmetric sizing area; the solution is shunted by the shunting bridge and enters the shunting holes, then enters the welding chamber and finally flows out through the core hole, and backward spiral cooling liquid is distributed around the male die and the female die, so that the solid phase rate of the solution is controlled.

The specific operation process comprises the following steps: the magnesium alloy solution enters an extrusion die through a wrap angle of 90 degrees, the semi-solid solution is introduced into a shunting region D1 in the convex die through a shunting chamber, the solution is shunted in the shunting region, so that the metal flows uniformly, the solution flows to a vertically asymmetric shearing region D2 through the shunting region D1, and the upper surface and the lower surface of the solution generate reasonable differential flow due to the staggered cross sections on the upper surface and the lower surface of the D2, so that a vortex is generated to form the shearing region; the solution enters an annular belt sizing area D3 with the same upper and lower sections for finishing through a shearing area D2; therefore, the magnesium alloy blank sequentially passes through the diversion region D1, the shearing region D2 and the sizing region D3 to form a tube blank with high surface quality and uniform structure.

The invention has the advantages and positive effects that: the texture distribution is improved, the anisotropy is weakened, the plastic forming capability of the product is improved, and the energy is saved; has the advantages of high productivity, good quality, strong flexibility and stable production and positive effects.

Drawings

FIG. 1 is a schematic view of a semi-solid magnesium alloy gradient extrusion combined die;

FIG. 2 is a schematic view of a male mold;

FIG. 3 is a cross-sectional view taken along the line A of the male mold;

FIG. 4 is a schematic view of a female mold;

FIG. 5 is a sectional view of the female mold B;

FIG. 6 is a schematic view of the male and female dies;

FIG. 7 is a cross-sectional view taken along the direction C for the mating of the male and female dies;

FIG. 8 is a schematic view of an action zone;

FIG. 9 is an enlarged view of a portion of FIG. 8;

in the figure: 1. a support plate; 2. a shunting chamber; 3. a temperature control chamber; 4. a male die; 5. a female die; 6. a core rod; 7. a spiral water passage opening; 8. a support; 9. a base; 10. a shunt bridge; 11. a core; 12. a shunt hole; 13. a welding chamber; 14. and (4) core holes.

Detailed Description

The invention will be explained with reference to the accompanying drawings, as shown in fig. 1, in the semisolid magnesium alloy gradient extrusion combined die provided by the invention, the left side of a supporting plate 1 is fixedly connected with a frame, the right side of the supporting plate is connected with a temperature control chamber 3 through a bolt, the inside of the temperature control chamber is connected with a shunting chamber 2, a male die 4 and a female die 5, the supporting plate 1 is connected with the shunting chamber 2 through a bolt, the right side of the shunting chamber 2 is connected with the male die 4 and the female die 5 in a matching way, the right end of the temperature control chamber 3 is connected with a support 8, the support 8 is connected with the female die 5 in a matching way, the; 2-7, the outer side of the mandrel 6 and the inner sides of the punch 4 and the die 5 form a shunting area D1 with equal spacing, a shearing area D2 with different spacing and a sizing area D3 with equal spacing, as shown in FIGS. 2-7; the first section is a shunting area formed by gradually reducing the inner diameter from left to right, the second section is a vertically asymmetric shearing area, and the third section is a vertically symmetric sizing area; backward spiral cooling liquid is distributed around the male die 4 and the female die 5, so that the solid phase rate of the solution is controlled; the magnesium alloy solution enters an extrusion die through a wrap angle of 90 degrees, the semi-solid solution is introduced into a shunting region D1 in the male die 4 through the shunting chamber 2, the solution is shunted and relaxed in the shunting region, so that the metal flows uniformly, and the solution flows to an upper asymmetric shearing region D2 through the shunting region D1, and the upper surface and the lower surface of the solution generate reasonable differential flow due to the staggered cross sections on the upper surface and the lower surface of D2, so that a vortex is generated to form the shearing region; the solution enters an annular belt sizing area D3 with the same upper and lower sections for finishing through a shearing area D2.

As shown in fig. 8 and 9, the inner wall of the shearing section D2 is a gradient corrugated strip, D is the extruded thickness,is the diameter of an extrusion cylinder and the diameter of a pipe after extrusion,the method comprises the steps of extruding the extruded pipe, wherein the thickness of the extruded pipe is the extrusion ratio, R is an arc-shaped band, D1 is a transverse gradient band, D2 is a turbulent band, D3 is a slow flow band, D4 is the length of a branch area, D is the gradient quantity, D = D1-D4, D1 ~ D4 is determined by the extrusion thickness D, R changes along with the change of D, and the extrusion width-to-width ratio

. Therefore, the magnesium alloy blank sequentially passes through the diversion region D1, the shearing region D2 and the sizing region D3 to form a tube blank with high surface quality and uniform structure.

Claims

1. A semi-solid magnesium alloy gradient extrusion combined die structurally comprises: the device comprises a supporting plate, a shunting chamber, a temperature control chamber, a male die, a female die, a core rod, a spiral water through hole, a support, a base, a shunting bridge, a mold core, shunting holes, a welding chamber and core holes; the device is characterized in that the left side of a supporting plate is fixedly connected with a frame of a casting and rolling machine through a bolt, the right side of the supporting plate is connected with a temperature control chamber through a bolt, the interior of the temperature control chamber is connected with a shunting chamber, a male die and a female die in an interference fit manner, the supporting plate is connected with the shunting chamber through a bolt, the right side of the shunting chamber is connected with the male die and the female die in a clearance fit manner, the right end of the temperature control chamber is connected with a support through a bolt, the support is; i.e. the core is in interference fit with the core hole.

2. The semi-solid magnesium alloy gradient extrusion combined die of claim 1, wherein: the outer side of the mandrel and the inner sides of the male die and the female die form a shunting area D1 with equal intervals, a shearing area D2 with different intervals and an extrusion cavity sizing area D3 with equal intervals; the first section is a shunting area formed by gradually reducing the inner diameter from left to right, the second section is a vertically asymmetric shearing area, and the third section is a vertically symmetric sizing area; the inner side of the extrusion die adopts a replaceable contact lantern ring; and the periphery of the male die 4 and the female die 5 is subjected to backward spiral cooling.