CN110560500B - Synchronous extruding and twisting composite device for screw-driven fine-grain magnesium alloy and processing method - Google Patents
Synchronous extruding and twisting composite device for screw-driven fine-grain magnesium alloy and processing method Download PDFInfo
- Publication number
- CN110560500B CN110560500B CN201910797467.6A CN201910797467A CN110560500B CN 110560500 B CN110560500 B CN 110560500B CN 201910797467 A CN201910797467 A CN 201910797467A CN 110560500 B CN110560500 B CN 110560500B
- Authority
- CN
- China
- Prior art keywords
- magnesium alloy
- extrusion
- alloy blank
- extruding
- screw
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C23/00—Extruding metal; Impact extrusion
- B21C23/001—Extruding metal; Impact extrusion to improve the material properties, e.g. lateral extrusion
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C23/00—Extruding metal; Impact extrusion
- B21C23/21—Presses specially adapted for extruding metal
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C23/00—Extruding metal; Impact extrusion
- B21C23/21—Presses specially adapted for extruding metal
- B21C23/212—Details
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C25/00—Profiling tools for metal extruding
- B21C25/02—Dies
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C29/00—Cooling or heating work or parts of the extrusion press; Gas treatment of work
- B21C29/003—Cooling or heating of work
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C43/00—Devices for cleaning metal products combined with or specially adapted for use with machines or apparatus provided for in this subclass
Abstract
The invention discloses a screw-driven fine-grain magnesium alloy synchronous extruding and twisting composite device and a processing method, and relates to the technical field of magnesium alloy application. Including base and magnesium alloy blank, the inboard middle part upper end of base is equipped with the extrusion die, the lower extreme of extrusion die rotates through roller bearing and is connected with the crowded die of turning round of variable cross section, magnesium alloy blank locates the extrusion die and the crowded inside of turning round the die of variable cross section, sliding connection has the extrusion terrace die directly over the inboard upper end of extrusion die and magnesium alloy blank, the crowded inboard lower extreme middle part of turning round the die of variable cross section has seted up the discharge gate, the crowded bottom of turning round the die of variable cross section is through the synchronous torsion device of locating pin nail fixedly connected with. The screw-driven fine-grain magnesium alloy synchronous extruding and twisting composite device realizes a severe plastic deformation process which is carried out synchronously by extruding and twisting, and ensures the deformation uniformity of a magnesium alloy blank in the process of fully refining grains.
Description
Technical Field
The invention relates to the technical field of magnesium alloy application, in particular to a screw-driven fine-grain magnesium alloy synchronous extruding and twisting composite device and a processing method.
Background
As a light structural material, the magnesium alloy has the characteristics of low density, high specific strength, high specific rigidity, good electromagnetic shielding performance and the like, thereby showing wide application prospects in national industry and daily production. However, because the magnesium alloy has a close-packed hexagonal structure, only two sliding systems can start at room temperature, so that the plastic deformation capacity of the magnesium alloy is poor, and further processing forming and engineering application of the magnesium alloy are greatly influenced. In order to overcome the technical problem, many researches are focused on improving the comprehensive mechanical properties of the magnesium alloy. In general, there are two main research directions at present, firstly, the design of a new alloy system is realized by adding rare earth elements, so that the material performance meets certain requirements, and secondly, the crystal grains are greatly refined by carrying out severe plastic deformation on the material. However, since rare earth elements are expensive, the addition of rare earth elements not only increases the production cost, but also easily causes casting defects during the production process, which is very disadvantageous for the subsequent processing and production.
It is well known that material properties are closely related to their microstructure. Generally, the smaller the average grain size of the material, the better the overall mechanical properties. Therefore, it is an effective method to improve the properties of magnesium alloy by subjecting the material to severe plastic deformation. At present, the severe plastic deformation of the material generally includes equal channel angular extrusion, high-pressure torsion, cumulative lap rolling and the like. As a novel plastic deformation method, severe plastic deformation can combine various deformation modes in the deformation process, and a large amount of strain is introduced, so that crystal grains are greatly refined, and basal plane texture is weakened, thereby greatly improving the mechanical property and the forming property of the material. Meanwhile, after deformation, a large sample with complete size can still be obtained, and the method has important significance in engineering practice. However, this method also has certain disadvantages and drawbacks, such as low processing efficiency and inability to achieve continuous production. Moreover, due to the complex deformation mode, the precise control is difficult to realize in the actual production process, which limits the application of the method to a certain extent.
Disclosure of Invention
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides a synchronous extruding and twisting composite device and a processing method for a spiral transmission fine-grain magnesium alloy, which have the advantages of grain refinement, texture weakening, continuous and accurate processing and the like, and solve the problems that the existing processing method is low in efficiency and cannot realize continuous production.
(II) technical scheme
In order to achieve the purposes of refining grains and weakening texture and realizing continuous and accurate processing, the invention provides the following technical scheme: a screw-driven fine-grained magnesium alloy synchronous extruding and twisting composite device comprises a base and a magnesium alloy blank, wherein an extruding female die is arranged at the upper end of the middle part of the inner side of the base, the lower end of the extruding female die is rotatably connected with a variable-section extruding and twisting female die through a roller bearing, the magnesium alloy blank is arranged in the extruding female die and the variable-section extruding and twisting female die, an extruding male die is slidably connected to the upper end of the inner side of the extruding female die and right above the magnesium alloy blank, a discharge hole is formed in the middle part of the lower end of the inner side of the variable-section extruding and twisting female die, the bottom of the variable-section extruding and twisting female die is fixedly connected with a synchronous twisting device through a positioning pin, a gear transmission shaft is arranged in the middle of the synchronous twisting device, a transmission gear is fixedly connected to the outer side of the gear transmission shaft, lead screws are respectively arranged on the left side and the right side of the inner part of the base, and the upper end and the lower end of each lead screw are respectively in threaded connection with an upper locking screw and a lower locking screw, the screw rod is in threaded connection with a screw transmission mechanism, the screw transmission mechanism mainly comprises a nut in threaded connection with the screw rod, a transmission gear is also fixedly connected to the outer side of the nut, and the transmission gear on the outer side of the gear transmission shaft is in meshed connection with the transmission gear on the outer side of the nut.
As a preferred technical scheme of the invention, a heating resistance wire is arranged in a die body of the extrusion female die.
As a preferred technical scheme of the invention, the upper end of the variable cross-section extruding-twisting female die is a circular cross section, and the lower end of the variable cross-section extruding-twisting female die is a polygonal cross section.
A processing method of a screw-driven fine-grain magnesium alloy synchronous extruding and twisting composite device comprises the following steps:
s1, selecting materials: solid block magnesium alloy blank, solid sand paper, solid powder high-temperature graphite, liquid absolute ethyl alcohol and liquid acetone;
s2, preprocessing one: polishing the magnesium alloy blank by using coarse abrasive paper, removing surface impurities and burrs, and sequentially polishing by using fine abrasive paper with different meshes in the order from small to large;
s3, preprocessing II: preparing a blank cleaning solution, wherein the ratio of the cleaning solution to acetone to absolute ethyl alcohol is =3:2, stirring uniformly after the preparation is finished, putting the blank into a cleaning tank, placing the magnesium alloy blank into the cleaning tank, then placing the cleaning tank on an ultrasonic cleaning machine, cleaning for 30min, and then drying by using a blower to dry;
s4, preprocessing three: debugging and starting a vacuum heating furnace, when the indication shows that the temperature reaches the preset temperature of 200-;
s5, installation and debugging device: firstly, completely coating lubricating graphite powder on the inner side of an extrusion female die, the inner side of a variable cross-section extrusion-torsion female die and other places which are contacted with a magnesium alloy blank, after the uniform coating, fixing the extrusion male die and the extrusion female die on an upper beam of a press machine, opening a fastening nut at the upper end of a lead screw, then installing the variable cross-section extrusion-torsion female die, a transmission gear and the like on a working platform together, accurately centering by using a positioning pin, then installing a roller bearing, connecting the extrusion female die, then locking a fixing screw at the upper end, then placing the nut at a position which is parallel to the transmission gear, fixing the movement of the nut in the vertical direction, finally opening the press machine, starting debugging the speed and the stroke of the press machine, and determining the proper extrusion height and extrusion speed;
s6, charging and heating: before the press machine starts, filling the magnesium alloy blank to a specified position, starting the heating resistance wire to enable the magnesium alloy blank to reach a preset temperature of 200-;
s7, extrusion: firstly, a cross beam of a press machine drives an extrusion convex die and a lead screw to simultaneously move downwards, the lead screw drives a nut to perform rotary motion, a transmission gear starts to work, when the extrusion convex die is contacted with a magnesium alloy blank, an extrusion stroke is started, the convex die moves downwards, the magnesium alloy blank enters a variable cross-section extrusion-torsion concave die, and the magnesium alloy blank starts to perform synchronous torsion deformation;
s8, discharging and subsequent processing: after the extrusion process is completed, the press machine moves upwards to drive the screw transmission mechanism and the synchronous extrusion torsion device to return to the initial position, the magnesium alloy blank is sawed off from the bottom end of the discharge port by a saw blade, the deformed magnesium alloy blank is taken out, the magnesium alloy blank is still cleaned by cleaning liquid and is subjected to cleaning treatment, the magnesium alloy blank is dried by cold air of a blower, the mark is made, and the processing is completed.
In a preferred embodiment of the present invention, in S4, the heating temperature of the vacuum heating furnace is 200-500 ℃.
In a preferred embodiment of the present invention, in S6, before the press is started, the magnesium alloy billet is coated with the lubricating graphite.
(III) advantageous effects
Compared with the prior art, the invention provides a synchronous extruding and twisting composite device and a processing method for the spiral transmission fine-grain magnesium alloy, and the device and the processing method have the following beneficial effects:
1. the screw-driven synchronous extruding and twisting composite device for the fine-grain magnesium alloy realizes an acute plastic deformation process for synchronously extruding and twisting, ensures the deformation uniformity of a magnesium alloy blank in the process of fully refining grains, effectively weakens the texture, reduces the anisotropy, and thus improves the comprehensive mechanical property of the magnesium alloy.
2. The screw-driven fine-grain magnesium alloy synchronous squeezing and twisting composite device adopts a mechanical transmission mode that a screw transmission mechanism is matched with a transmission gear, the process is flexible and changeable, different types of screw transmission mechanisms can be used, the meshing mode and the transmission ratio of the transmission gear can be changed, and the rotation speed and further the twisting speed can be adjusted.
3. The synchronous extruding and twisting composite device for the screw-driven fine-grained magnesium alloy can realize extrusion of different section shapes through the variable-section extruding and twisting female die, namely can realize extrusion of section bars with different section shapes through designing and replacing the shape of a variable-section extruding and twisting female die channel, and greatly improves the application range of the device.
4. The processing method of the screw-driven fine-grain magnesium alloy synchronous extruding and twisting composite device is based on mechanical transmission components such as screw drive, gear drive and the like, so that the size specification and key technical parameters of transmission parts are reasonably designed, the continuous processing production of large-scale magnesium alloy blanks can be realized, and the processing method has important significance for industrial application.
Drawings
FIG. 1 is an extrusion state diagram of a screw-driven fine-grained magnesium alloy synchronous extrusion-torsion composite device and a processing method thereof;
FIG. 2 is a top view of a gear transmission device and a nut of the screw-driven fine-grained magnesium alloy synchronous extrusion-torsion composite device provided by the invention;
fig. 3 is a schematic deformation diagram of a magnesium alloy blank of a screw-driven fine-grain magnesium alloy synchronous extrusion-torsion composite device provided by the invention.
In the figure: 1. a lower end locking screw; 2. a screw drive mechanism; 3. a lead screw; 4. positioning a pin; 5. a roller bearing; 6. extruding the female die; 7. the upper end is locked by a screw; 8. extruding the male die; 9. a magnesium alloy blank; 10. heating resistance wires; 11. a variable cross-section extruding-twisting female die; 12. a discharge port; 13. a synchronous torsion device; 14. a nut; 15. a transmission gear; 16. a gear transmission shaft; 17. a base.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-3, a synchronous extruding-twisting composite device and a processing method for a screw-driven fine-grained magnesium alloy comprise a base 17 and a magnesium alloy blank 9, wherein an extruding female die 6 is arranged at the upper end of the middle part of the inner side of the base 17, the lower end of the extruding female die 6 is rotatably connected with a variable cross-section extruding-twisting female die 11 through a roller bearing 5, the upper end of the variable cross-section extruding-twisting female die 11 is a circular cross section and a polygonal cross section at the lower end, the magnesium alloy blank 9 is arranged inside the extruding female die 6 and the variable cross-section extruding-twisting female die 11, an extruding male die 8 is slidably connected at the upper end of the inner side of the extruding female die 6 and right above the magnesium alloy blank 9, a discharge hole 12 is formed in the middle part of the lower end of the inner side of the variable cross-section extruding-twisting female die 11, a synchronous twisting device 13 is fixedly connected at the bottom of the variable cross-section extruding-twisting female die 11 through a positioning pin 4, and a gear transmission shaft 16 is arranged in the middle part of the synchronous twisting device 13, the outer side of the gear transmission shaft 16 is fixedly connected with a transmission gear 15, the left side and the right side of the inside of the base 17 are provided with a lead screw 3, the upper end and the lower end of the lead screw 3 are respectively in threaded connection with an upper locking screw 7 and a lower locking screw 1, the lead screw 3 is provided with a screw transmission mechanism 2, the screw transmission mechanism 2 mainly comprises a nut 14 in threaded connection with the lead screw 3, the outer side of the nut 14 is also fixedly connected with a transmission gear 15, and the transmission gear 15 on the outer side of the gear transmission shaft 16 is in meshed connection with the transmission gear 15 on the outer side of the nut 14.
As a specific technical scheme of this embodiment, a heating resistance wire 10 is disposed in a die body of the extrusion female die 6.
In this embodiment, the heating resistance wire 10 is convenient for heating the magnesium alloy blank 9, and is convenient for shaping.
The first embodiment is as follows:
a processing method of a screw-driven fine-grain magnesium alloy synchronous extruding and twisting composite device comprises the following steps:
s1, selecting materials: the solid block magnesium alloy blank 9 is a magnesium alloy round section bar material AZ31, the diameter is phi 80mm, the length is 100mm, the magnesium content is 95%, the aluminum content is 3.0%, the zinc content is 1.0%, the rest is elements such as Mn, Fe and the like, the solid sand paper is made of SiC particles, the mesh number is 600#, 1000#, 1200#, 2500# in sequence from small to large, the high-temperature graphite of solid powder, 99.5% absolute ethyl alcohol of 1200ml of liquid, and 99% acetone of 800ml of liquid;
s2, preprocessing one: polishing the magnesium alloy blank 9 by using coarse abrasive paper to remove surface impurities and burrs, and then sequentially polishing by using fine abrasive paper with different meshes in the order from small to large to remove a surface oxide layer of the magnesium alloy blank 9 so as to reduce friction;
s3, preprocessing II: preparing a blank cleaning solution, wherein the ratio of the cleaning solution to acetone to absolute ethyl alcohol is =3:2, stirring uniformly after the preparation is finished, putting the blank into a cleaning tank, placing the magnesium alloy blank 9 into the cleaning tank, then placing the cleaning tank on an ultrasonic cleaning machine, cleaning for 30min, and then drying by using a cold air blower;
s4, preprocessing three: debugging and starting a vacuum heating furnace, setting the heating temperature of the vacuum heating furnace to be 350 ℃, putting the magnesium alloy blank 9 into the center of a hearth when the reading shows that the preset temperature is reached, so as to ensure that the magnesium alloy blank 9 is uniformly heated, starting timing after the temperature in the furnace is kept stable, and keeping the temperature for 2 hours;
s5, installation and debugging device: firstly, lubricating graphite powder is completely coated on the inner side of an extrusion female die 6, the inner side of a variable cross-section extrusion female die 11 and the like which are contacted with a magnesium alloy blank 9, after the uniform coating, an extrusion male die 8 and the extrusion female die 6 are fixed on an upper beam of a press, a fastening nut 7 at the upper end of a lead screw 3 is opened, then the variable cross-section extrusion female die 11, a transmission gear 15 and the like are installed on a working platform together, a positioning pin 4 is used for accurate centering, then a roller bearing 5 is installed and connected with the extrusion female die 6, a fixing screw at the upper end is locked down, then a nut 14 is placed at a position which is parallel and level with the transmission gear 15, the vertical movement of the nut is fixed, finally the press is opened, the speed and the stroke of the press are adjusted, and the proper extrusion height and extrusion speed are determined;
s6, charging and heating: before the press is started, smearing lubricating graphite on the outer side of a magnesium alloy blank 9, filling the magnesium alloy blank 9 to a specified position, starting a heating resistance wire 10 to enable the magnesium alloy blank 9 to reach a preset temperature of 350 ℃, starting heat preservation and timing for 2 hours, and starting the press after the heat preservation time is reached;
s7, extrusion: firstly, a cross beam of a press machine drives an extrusion male die 8 and a lead screw 3 to simultaneously move downwards, the lead screw 3 drives a nut 14 to perform rotary motion, a transmission gear 15 starts to work, when the extrusion male die 8 is contacted with a magnesium alloy blank 9, an extrusion stroke is started, the male die moves downwards, the magnesium alloy blank 9 enters a variable cross-section extrusion-torsion female die 11, and the magnesium alloy blank 9 starts to perform synchronous torsion deformation;
s8, discharging and subsequent processing: after the extrusion process is completed, the press machine moves upwards to drive the screw transmission mechanism 2 and the synchronous extrusion torsion device to return to the initial position, the magnesium alloy blank 9 after deformation is taken out by sawing the bottom end of the discharge port 12 with a saw blade, the magnesium alloy blank is still cleaned with cleaning liquid and is subjected to cleaning treatment, the magnesium alloy blank is dried with cold air of a blower, and the mark is made and the processing is completed.
And (4) conclusion: through synchronous extrusion and torsion, the average grain size of the magnesium alloy blank 9 is remarkably reduced from 15.26 mu m of an original plate to 2.64 mu m, the texture strength is reduced from 20.38 to 11.408, all parts of the magnesium alloy blank 9 are uniformly deformed, the deformation coordination among all grains is fully improved, the texture strength is remarkably reduced, and the comprehensive mechanical property of the magnesium alloy is remarkably improved.
Example two:
a processing method of a screw-driven fine-grain magnesium alloy synchronous extruding and twisting composite device comprises the following steps:
s1, selecting materials: solid block magnesium alloy billet 9, AZ61 magnesium alloy square section bar with cross-sectional area of 60 x 60mm2The length of the abrasive paper is 100mm, the magnesium content is 92%, the aluminum content is 6.0%, the zinc content is 1.0%, and the balance is elements such as Mn, Fe and the like, the solid abrasive paper is made of SiC particles, the mesh number of the abrasive paper is 600#, 1000#, 1200#, 2500# in sequence from small to large, the high-temperature graphite of solid powder, 99.5% absolute ethyl alcohol of 1200ml of liquid, and 99% acetone of 800ml of liquid;
s2, preprocessing one: polishing the magnesium alloy blank 9 by using coarse abrasive paper to remove surface impurities and burrs, and then sequentially polishing by using fine abrasive paper with different meshes in the order from small to large to remove a surface oxide layer of the magnesium alloy blank 9 so as to reduce friction;
s3, preprocessing II: preparing a blank cleaning solution, wherein the ratio of the cleaning solution to acetone to absolute ethyl alcohol is =3:2, stirring uniformly after the preparation is finished, putting the blank into a cleaning tank, placing the magnesium alloy blank 9 into the cleaning tank, then placing the cleaning tank on an ultrasonic cleaning machine, cleaning for 30min, and then drying by using a cold air blower;
s4, preprocessing three: debugging and starting a vacuum heating furnace, setting the heating temperature of the vacuum heating furnace to be 300 ℃, putting the magnesium alloy blank 9 into the center of a hearth when the reading shows that the preset temperature is reached, so as to ensure that the magnesium alloy blank 9 is uniformly heated, starting timing after the temperature in the furnace is kept stable, and keeping the temperature for 2 hours;
s5, installation and debugging device: firstly, lubricating graphite powder is completely coated on the inner side of an extrusion female die 6, the inner side of a variable cross-section extrusion female die 11 and the like which are contacted with a magnesium alloy blank 9, after the uniform coating, an extrusion male die 8 and the extrusion female die 6 are fixed on an upper beam of a press, a fastening nut at the upper end of a lead screw 3 is opened, a transmission gear 15 and the like are installed on a working platform together, a positioning pin 4 is used for accurate centering, a roller bearing 5 is installed and connected with the extrusion female die 6, the upper end fixing screw is locked down, a nut 14 is placed at a position which is parallel to and level with the transmission gear 15, the vertical movement of the nut is fixed, finally the press is opened, the speed and the stroke of the press are adjusted, and the proper extrusion height and extrusion speed are determined;
s6, charging and heating: before the press is started, smearing lubricating graphite on the outer side of a magnesium alloy blank 9, filling the magnesium alloy blank 9 to a specified position, starting a heating resistance wire 10 to enable the magnesium alloy blank 9 to reach a preset temperature of 300 ℃, starting heat preservation and timing for 2 hours, and starting the press after the heat preservation time is reached;
s7, extrusion: firstly, a cross beam of a press machine drives an extrusion male die 8 and a lead screw 3 to simultaneously move downwards, the lead screw 3 drives a nut 14 to perform rotary motion, a transmission gear 15 starts to work, when the extrusion male die 8 is contacted with a magnesium alloy blank 9, an extrusion stroke is started, the male die moves downwards, the magnesium alloy blank 9 enters a variable cross-section extrusion-torsion female die 11, and the magnesium alloy blank 9 starts to perform synchronous torsion deformation;
s8, discharging and subsequent processing: after the extrusion process is completed, the press machine moves upwards to drive the screw transmission mechanism 2 and the synchronous extrusion torsion device to return to the initial position, the magnesium alloy blank 9 after deformation is taken out by sawing the bottom end of the discharge port 12 with a saw blade, the magnesium alloy blank is still cleaned with cleaning liquid and is subjected to cleaning treatment, the magnesium alloy blank is dried with cold air of a blower, and the mark is made and the processing is completed.
And (4) conclusion: through synchronous extrusion and torsion, the average grain size of the magnesium alloy blank 9 is obviously reduced, the average grain size is reduced to 1.42 mu m from 12.86 mu m of an original plate, the texture strength is reduced to 5.58 from 22.32, all parts of the magnesium alloy blank 9 are uniformly deformed, the deformation coordination among all grains is fully improved, the texture strength is obviously reduced, and the comprehensive mechanical property of the magnesium alloy is obviously improved.
Example three:
a processing method of a screw-driven fine-grain magnesium alloy synchronous extruding and twisting composite device comprises the following steps:
s1, selecting materials: the solid block magnesium alloy ingot is a solid block magnesium alloy blank 9, a Mg-8Li-1Al-1Zn alloy circular ingot, the diameter of which is phi 100mm, the length of which is 100mm, the magnesium content of which is 95 percent, the lithium content of which is 8.0 percent, the aluminum content of which is 1.0 percent, the zinc content of which is 1.0 percent, and the balance of elements such as Mn, Fe and the like, sand paper of solid is made of SiC particles, the mesh number of which is 600#, 1000#, 1200#, 2500# in sequence from small to large, high-temperature graphite of solid powder, 99.5 percent absolute ethyl alcohol of 1200ml of liquid, and 99 percent acetone of 800ml of liquid;
s2, preprocessing one: polishing the magnesium alloy blank 9 by using coarse abrasive paper to remove surface impurities and burrs, and then sequentially polishing by using fine abrasive paper with different meshes in the order from small to large to remove a surface oxide layer of the magnesium alloy blank 9 so as to reduce friction;
s3, preprocessing II: preparing a blank cleaning solution, wherein the ratio of the cleaning solution to acetone to absolute ethyl alcohol is =3:2, stirring uniformly after the preparation is finished, putting the blank into a cleaning tank, placing the magnesium alloy blank 9 into the cleaning tank, then placing the cleaning tank on an ultrasonic cleaning machine, cleaning for 30min, and then drying by using a cold air blower;
s4, preprocessing three: debugging and starting a vacuum heating furnace, setting the heating temperature of the vacuum heating furnace to be 400 ℃, putting the magnesium alloy blank 9 into the center of a hearth when the reading shows that the preset temperature is reached, so as to ensure that the magnesium alloy blank 9 is uniformly heated, starting timing after the temperature in the furnace is kept stable, and keeping the temperature for 1.5 h;
s5, installation and debugging device: firstly, lubricating graphite powder is completely coated on the inner side of an extrusion female die 6, the inner side of a variable cross-section extrusion female die 11 and the like which are contacted with a magnesium alloy blank 9, after the uniform coating, an extrusion male die 8 and the extrusion female die 6 are fixed on an upper beam of a press, a fastening nut 7 at the upper end of a lead screw 3 is opened, then the variable cross-section extrusion female die 11, a transmission gear 15 and the like are installed on a working platform together, a positioning pin 4 is used for accurate centering, then a roller bearing 5 is installed and connected with the extrusion female die 6, a fixing screw at the upper end is locked down, then a nut 14 is placed at a position which is parallel and level with the transmission gear 15, the vertical movement of the nut is fixed, finally the press is opened, the speed and the stroke of the press are adjusted, and the proper extrusion height and extrusion speed are determined;
s6, charging and heating: before the press is started, smearing lubricating graphite on the outer side of a magnesium alloy blank 9, filling the magnesium alloy blank 9 to a specified position, starting a heating resistance wire 10 to enable the magnesium alloy blank 9 to reach a preset temperature of 400 ℃, starting heat preservation and timing for 1.5h, and starting the press after the heat preservation time is reached;
s7, extrusion: firstly, a cross beam of a press machine drives an extrusion male die 8 and a lead screw 3 to simultaneously move downwards, the lead screw 3 drives a nut 14 to perform rotary motion, a transmission gear 15 starts to work, when the extrusion male die 8 is contacted with a magnesium alloy blank 9, an extrusion stroke is started, the male die moves downwards, the magnesium alloy blank 9 enters a variable cross-section extrusion-torsion female die 11, and the magnesium alloy blank 9 starts to perform synchronous torsion deformation;
s8, discharging and subsequent processing: after the extrusion process is completed, the press machine moves upwards to drive the screw transmission mechanism 2 and the synchronous extrusion torsion device to return to the initial position, the magnesium alloy blank 9 after deformation is taken out by sawing the bottom end of the discharge port 12 with a saw blade, the magnesium alloy blank is still cleaned with cleaning liquid and is subjected to cleaning treatment, the magnesium alloy blank is dried with cold air of a blower, and the mark is made and the processing is completed.
And (4) conclusion: through synchronous extrusion and torsion, the average grain size of the magnesium alloy blank 9 is remarkably reduced, the average grain size is reduced to 2.64 mu m from 110.86 mu m of an original plate, the texture strength of a basal plane is reduced to 7.84 from 16.68, all parts of the magnesium alloy blank 9 are uniformly deformed, the deformation coordination among all grains is fully improved, the texture strength is remarkably reduced, and the comprehensive mechanical property of the magnesium alloy is remarkably improved.
The working principle of the invention is as follows: firstly, in the descending process of a press, a cross beam drives an extrusion male die 8 and a lead screw 3 to descend simultaneously, the lead screw 3 drives a nut 14 to perform rotary motion, a transmission gear 15 starts to work, so that the first batch of processed materials are formed by synchronous extrusion-torsion composite action, when the extrusion male die 8 is contacted with a magnesium alloy blank 9, a first extrusion stroke is started, in the process, the cross section area of a bar is unchanged, the magnesium alloy blank 9 is softened and flows due to heating, defects such as holes in the magnesium alloy blank 9 are effectively pressed, the extrusion male die 8 continues to descend, the magnesium alloy blank 9 enters a variable cross section extrusion female die 11, the magnesium alloy blank 9 is subjected to circumferential shearing force caused by the rotation of the transmission gear 15 while bearing the extrusion force of the extrusion male die 8, and the shearing force is continuously applied to each part of the magnesium alloy blank 9, the magnesium alloy blank 9 of each part is subjected to severe plastic deformation, meanwhile, the grain orientation in the material is changed continuously, the texture is weakened obviously, in the process, the shape of the magnesium alloy blank 9 is changed, the section of the magnesium alloy blank 9 is changed from a round shape to a square section or other polygonal sections, and the subsequent torsional deformation is performed smoothly.
It is to be noted that, in this document, terms such as "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (3)
1. A processing method of a screw-driven synchronous extruding-twisting composite device for fine-grained magnesium alloy is characterized by comprising the synchronous extruding-twisting composite device, wherein the synchronous extruding-twisting composite device comprises a base (17) and a magnesium alloy blank (9), an extruding female die (6) is arranged at the upper end of the middle part of the inner side of the base (17), the lower end of the extruding female die (6) is rotatably connected with a variable cross-section extruding-twisting female die (11) through a roller bearing (5), the magnesium alloy blank (9) is arranged in the extruding female die (6) and the variable cross-section extruding-twisting female die (11), an extruding male die (8) is slidably connected at the upper end of the inner side of the extruding female die (6) and right above the magnesium alloy blank (9), a discharge hole (12) is formed in the middle part of the lower end of the inner side of the variable cross-section extruding-twisting female die (11), and a synchronous twisting device (13) is fixedly connected at the bottom of the variable cross-section extruding-twisting female die (11) through a positioning pin (4), a gear transmission shaft (16) is arranged in the middle of the synchronous torsion device (13), a transmission gear (15) is fixedly connected to the outer side of the gear transmission shaft (16), lead screws (3) are mounted on the left side and the right side of the inside of the base (17), the upper end and the lower end of each lead screw (3) are respectively in threaded connection with an upper locking screw (7) and a lower locking screw (1), a screw transmission mechanism (2) is in threaded connection with each lead screw (3), each screw transmission mechanism (2) mainly comprises a transmission nut (14) in threaded connection with each lead screw (3), a transmission gear (15) is also fixedly connected to the outer side of each transmission nut (14), and the transmission gear (15) on the outer side of the gear transmission shaft (16) is in meshed connection with the transmission gear (15) on the outer side of each transmission nut (14);
the processing method of the screw-driven fine-grain magnesium alloy synchronous extruding and twisting composite device comprises the following steps:
s1, selecting materials: solid block magnesium alloy blank (9), solid sand paper, solid powder high-temperature graphite, liquid absolute ethyl alcohol and liquid acetone;
s2, preprocessing one: polishing the magnesium alloy blank (9) by using coarse abrasive paper to remove surface impurities and burrs, and then sequentially polishing by using fine abrasive paper with different meshes according to the order of the meshes from small to large;
s3, preprocessing II: preparing a blank cleaning solution, wherein the ratio of the cleaning solution to acetone to absolute ethyl alcohol is =3:2, stirring uniformly after the preparation is finished, putting the blank into a cleaning tank, putting the magnesium alloy blank (9) into the cleaning tank, then putting the cleaning tank on an ultrasonic cleaning machine, cleaning for 30min, and then drying by using a blower to dry with cold air;
s4, preprocessing three: debugging and starting the vacuum heating furnace, when the indication shows that the temperature reaches the preset temperature of 200-;
s5, installation and debugging device: firstly, lubricating graphite powder is completely coated on the inner side of an extrusion female die (6) and the inner side of a variable cross-section extrusion-torsion female die (11) in a contact position with a magnesium alloy blank (9), after the lubricating graphite powder is uniformly coated, the extrusion male die (8) and the extrusion female die (6) are fixed on an upper cross beam of a press machine, an upper end locking screw (7) of a lead screw (3) is opened, then the variable cross-section extrusion-torsion female die (11), a transmission gear (15) and a gear transmission shaft (16) are installed on a working platform together, the transmission gear (15) and the gear transmission shaft are accurately centered by a positioning pin (4), then a roller bearing (5) is installed and connected with the extrusion female die (6), then the upper end locking screw (7) is locked, then a transmission nut (14) is placed on a position which is parallel to the transmission gear (15) and fixes the movement of the transmission nut in the vertical direction, finally, the press machine is opened, and the speed of the press machine is started to be debugged, stroke to determine the appropriate extrusion height and extrusion rate;
s6, charging and heating: before the press machine starts, filling the magnesium alloy blank (9) to a specified position, starting the heating resistance wire (10) to enable the magnesium alloy blank (9) to reach a preset temperature of 200-;
s7, extrusion: firstly, a cross beam of a press machine drives an extrusion male die (8) and a lead screw (3) to simultaneously move downwards, the lead screw (3) drives a transmission nut (14) to perform rotary motion, a transmission gear (15) starts to work, after the extrusion male die (8) is contacted with a magnesium alloy blank (9), an extrusion stroke is started, the male die moves downwards, the magnesium alloy blank (9) enters a variable cross-section extrusion-torsion female die (11), and the magnesium alloy blank (9) starts to perform synchronous torsional deformation;
s8, discharging and subsequent processing: after the extrusion process is finished, the press machine moves upwards to drive the screw transmission mechanism (2) and the synchronous extrusion torsion device to return to the initial position, the magnesium alloy blank (9) after deformation is taken out by sawing the bottom end of the discharge port (12) with a saw blade, the magnesium alloy blank is still cleaned and cleaned with cleaning liquid, and the magnesium alloy blank is dried by cold air of a blower to be marked and processed.
2. The processing method of the screw-driven fine-grain magnesium alloy synchronous extrusion-torsion composite device according to claim 1, characterized in that: in the S4, the heating temperature of the vacuum heating furnace is set to be 200-500 ℃.
3. The processing method of the screw-driven fine-grain magnesium alloy synchronous extrusion-torsion composite device according to claim 1, characterized in that: in S6, before the press is started, lubricating graphite is coated on the outer side of the magnesium alloy blank (9).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910797467.6A CN110560500B (en) | 2019-08-27 | 2019-08-27 | Synchronous extruding and twisting composite device for screw-driven fine-grain magnesium alloy and processing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910797467.6A CN110560500B (en) | 2019-08-27 | 2019-08-27 | Synchronous extruding and twisting composite device for screw-driven fine-grain magnesium alloy and processing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110560500A CN110560500A (en) | 2019-12-13 |
| CN110560500B true CN110560500B (en) | 2021-12-31 |
Family
ID=68776309
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910797467.6A Active CN110560500B (en) | 2019-08-27 | 2019-08-27 | Synchronous extruding and twisting composite device for screw-driven fine-grain magnesium alloy and processing method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110560500B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112371743B (en) * | 2020-10-22 | 2023-01-24 | 烟台大学 | High-pressure torsion reciprocating extrusion processing device and processing method |
| CN112620372B (en) * | 2020-12-23 | 2022-05-24 | 太原理工大学 | Mold and method for preparing weak basal plane texture magnesium alloy plate strip through continuous differential extrusion |
| CN113234904B (en) * | 2021-05-10 | 2023-01-17 | 烟台大学 | High-flux preparation method and device of gradient material |
| CN113234905B (en) * | 2021-05-10 | 2023-06-13 | 烟台大学 | High-flux preparation method and device for gradient thermal deformation and gradient thermal treatment |
| CN114378128A (en) * | 2022-01-26 | 2022-04-22 | 重庆理工大学 | Integrated device for preparing light alloy thin-wall pipe and processing method thereof |
| CN115889486A (en) * | 2022-12-09 | 2023-04-04 | 哈尔滨理工大学 | Continuous variable cross-section profile extrusion forming device and method regulated and controlled by rotary moving die |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1165010A (en) * | 1966-12-22 | 1969-09-24 | William Shiel Caisley | Improvements in or relating to the Extrusion of Helically Fluted Cutting Tools. |
| JPS5844911A (en) * | 1981-09-11 | 1983-03-16 | Hitachi Ltd | Method and device for extrusion |
| UA31997U (en) * | 2008-01-03 | 2008-04-25 | Донецкий Физико-Технический Институт Им. А.А.Галкина Нан Украины | Device for intensive plastic deformation of materials by torsion under high pressure |
| RU2448794C2 (en) * | 2008-12-26 | 2012-04-27 | Учреждение Российской академии наук Институт физико-технических проблем Севера им. В.П.Ларионова Сибирского отделения РАН | Device for straining billets with producing combined intensive plastic deformation |
| CN107649527A (en) * | 2017-09-22 | 2018-02-02 | 哈尔滨工业大学 | A kind of Horizontal revolving-die extrusion molding apparatus for being used to improve product properties |
| CN109570253B (en) * | 2018-11-19 | 2020-03-31 | 北京科技大学 | Magnesium/aluminum alloy bimetal composite pipe forming die and method |
| CN109759488B (en) * | 2018-12-29 | 2019-11-22 | 华中科技大学 | A kind of high pressure torsion shaping dies |
-
2019
- 2019-08-27 CN CN201910797467.6A patent/CN110560500B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110560500A (en) | 2019-12-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110560500B (en) | Synchronous extruding and twisting composite device for screw-driven fine-grain magnesium alloy and processing method | |
| CN1298452C (en) | Continuously extruding method of magnesium alloy silk material | |
| CN110496868B (en) | Rotary reciprocating extrusion device and processing method for superfine crystal magnesium alloy | |
| WO2015035894A1 (en) | Method for producing profile for aircraft wing stringer | |
| CN102601141A (en) | Coextrusion processing method of magnesium alloy | |
| CN106140847A (en) | A kind of magnesium alloy compressional deformation processing unit (plant) and processing method | |
| CN1736913A (en) | Glass container production method | |
| CN100491005C (en) | Metallic extrusion molding method of rotating cavity die | |
| CN114411072B (en) | Aluminum alloy material with gradient structure and preparation method thereof | |
| CN113560362B (en) | High-performance magnesium alloy variable-section extrusion-torsion composite processing device and preparation process thereof | |
| CN108296299A (en) | Equal channels rotary squeezing prepares the device and method of high-performance magnesium-alloy | |
| CN109702025A (en) | A kind of reciprocating extrusion processing method of high-performance superfine grained magnesium alloy tubing | |
| CN104313423A (en) | Manufacturing method of Mg-based composite wallboard profile | |
| CN1282517C (en) | Manufacturing method of electrode cap used for welding automobile coated steel plate | |
| CN110508635B (en) | Asymmetric reciprocating extrusion device with separated male die and machining method | |
| CN112356245A (en) | Blank trimming device for graphite crucible | |
| CN1693012A (en) | Method for founding aluminium alloy slab ingot | |
| CN110983266A (en) | Rotary sputtering target material and preparation method thereof | |
| CN1775993A (en) | Method for preparing micron fine-crystal titanium-nickle-hafnium high-temp. shape memory alloy cube matherial | |
| CN107570962B (en) | A kind of aluminium alloy extrusions and preparation method thereof for producing attachments of a bicycle | |
| CN111958193B (en) | Preparation method of alloy wire difficult to deform | |
| CN112845644B (en) | Device and method for preparing pure nickel N6 bar surface gradient structure | |
| CN206716929U (en) | A kind of isometric continuous shearing shaping device repeatedly of metal | |
| CN108246943B (en) | Method for forming prefabricated blank of cylindrical helical gear | |
| CN220028649U (en) | Mould that aluminium bar was convenient for drawing of patterns |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |