CN112481456A - Reciprocating electric pulse auxiliary rolling heat treatment device and method - Google Patents

Reciprocating electric pulse auxiliary rolling heat treatment device and method Download PDF

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Publication number
CN112481456A
CN112481456A CN202011222807.1A CN202011222807A CN112481456A CN 112481456 A CN112481456 A CN 112481456A CN 202011222807 A CN202011222807 A CN 202011222807A CN 112481456 A CN112481456 A CN 112481456A
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rolling
metal plate
heat treatment
electric
pulse
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湛利华
彭南辉
曾泉清
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Central South University
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Central South University
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/34—Methods of heating
    • C21D1/40—Direct resistance heating
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Control Of Resistance Heating (AREA)
  • Heat Treatment Of Articles (AREA)

Abstract

The invention discloses a reciprocating electric pulse auxiliary rolling heat treatment device and a reciprocating electric pulse auxiliary rolling heat treatment method, wherein the heat treatment method comprises the following steps: placing a metal plate to be processed on a machine base of a heat treatment device, and clamping and fixing the metal plate by using a blank holder; respectively contacting electric brush heads of the anode electric brush and the cathode electric brush with the edge of the metal plate; applying electric pulse to the metal plate by using the electric pulse, starting to perform reciprocating rolling on the metal plate by using the rolling head at the same time, and stopping the electric pulse and the rolling when the metal material reaches the performance corresponding to the heat treatment of the metal material; and cooling the metal plate subjected to rolling treatment to room temperature. According to the heat treatment method, the electric pulse treatment device and the rolling device are used for simultaneously applying the pulse electric field and the circulating stress field to the metal plate, so that the diffusion rate of solute atoms is increased, the uniformity of precipitated phases, the precipitation speed and the precipitation quantity are enhanced, the energy consumption is reduced, the quality and the efficiency of metal heat treatment are improved, and the production cost is reduced.

Description

Reciprocating electric pulse auxiliary rolling heat treatment device and method
Technical Field
The invention relates to the technical field of heat treatment, in particular to a reciprocating electric pulse auxiliary rolling heat treatment device and method.
Background
The metal heat treatment is a technological means for regulating and controlling the phase transformation, precipitation and phase composition of metal or alloy so as to obtain different tissue structures and optimize the material performance. Bulk heat treatment is the most common heat treatment process and mainly comprises quenching, tempering, normalizing, annealing and other forms used in cooperation therewith. The technological process includes heating metal material to certain temperature, maintaining for certain time to promote element diffusion, and cooling with different medium (water, oil and air). During heat treatment, the control of the tissue structure and the performance is realized by controlling the heating temperature, the heating speed, the cooling speed and the heat preservation time. In a conventional heat treatment method, a plurality of workpieces are generally arranged in a heat treatment furnace with a shell, the workpieces are mainly heated by heat radiation and heat conduction, the heat transmission speed is low, the dissipation is high, and the heating time is often long. Meanwhile, when the large workpiece is subjected to heat treatment, the problem of uneven heating of the workpiece is particularly obvious, and the conditions of poor uniformity of material structure and poor performance consistency after the heat treatment are obvious. In addition, the traditional heat treatment process is complex, and the problems of environmental pollution and the like are easily caused.
The electric pulse treatment is used as a novel technical means for improving the performance of solid metal, a workpiece can be rapidly heated by virtue of joule heat, and meanwhile, the thermal expansion of the material lags behind the temperature rise due to the strong interaction between the electron current and atoms, so that the formed instantaneous hot-pressing stress is beneficial to improving the microstructure. Patent numbers: 2018113527247 discloses an electric pulse assisted hot extrusion method. The invention can obviously reduce the forming pressure, refine the crystal grains and improve the product quality. Patent numbers: 201910812095X combines the traditional heating mode with electric pulse, and provides a heat-assisted electric pulse treatment method which can reduce the influence of the temperature rise process on the structure of the metal material and can provide a relatively stable temperature field. The electric pulse is introduced into the above patents, the microstructure performance of the material is improved to a certain extent, but the time and the temperature assisted by the electric pulse are consistent with the conventional heat treatment time, the consumed time is long, the production efficiency is reduced, and huge heating energy consumption is also caused.
Therefore, it is important to provide a heat treatment apparatus and method which can improve the formability and reduce the cost.
Disclosure of Invention
The invention aims to provide a reciprocating electric pulse auxiliary rolling heat treatment device and a reciprocating electric pulse auxiliary rolling heat treatment method, so as to solve the problems in the prior art. During heat treatment, an electric pulse treatment device and a rolling device are used for simultaneously applying a pulse electric field and a circulating stress field to the metal plate, so that the diffusion rate of solute atoms is increased, the uniformity of precipitated phases, the precipitation speed and the precipitation quantity are strengthened, the energy consumption is reduced, the quality and the efficiency of metal heat treatment are improved, and the production cost is reduced.
In order to achieve the purpose, the invention provides the following technical scheme:
the invention provides a reciprocating electric pulse auxiliary rolling heat treatment device which comprises an alternating current power supply, a controller, a base, a blank holder, an electric pulse treatment device and a rolling device, wherein the blank holder is arranged on the base and used for pressing a metal plate to be treated on the base; the electric pulse processing device comprises a pulse rectifier, an anode electric brush and a cathode electric brush, wherein electric brush heads of the anode electric brush and the cathode electric brush are respectively used for being in contact with two ends of the metal plate; the alternating current power supply is connected with the controller, the controller is respectively connected with the rolling device and the pulse rectifier, and the pulse rectifier is respectively connected with the anode electric brush and the cathode electric brush; the rolling device is arranged above the base and used for performing reciprocating rolling on the metal plate placed on the base.
The edge pressing device comprises at least two edge pressing seats arranged at two ends of the base, one edge pressing slide bar is arranged on one side, close to the metal sheet, of each edge pressing seat, an edge pressing screw rod connected with the edge pressing slide bars penetrates through the edge pressing seats, and the edge pressing screw rod is used for controlling the size of pressing force of the edge pressing slide bars on the metal sheet.
Furthermore, an opening is formed in the bottom of one side, close to the metal plate, of the edge pressing seat, and one end of the edge pressing sliding strip extends into the opening and is fixedly connected with the lower end of the edge pressing screw rod.
Furthermore, rubber pads are arranged on the machine base and the parts of the edge pressing sliding strips, which are used for being in contact with the metal plate materials.
Furthermore, the two ends of the machine base are respectively provided with a wire clamping seat, and a wire clamping sleeve is arranged on the wire clamping seat.
Furthermore, the rolling device comprises a retainer, a rolling head support and a rolling head, wherein the rolling head support is arranged at the bottom of the retainer, and the rolling head is arranged in the rolling head support.
The invention also provides a reciprocating electric pulse auxiliary rolling heat treatment method based on the heat treatment device, which comprises the following steps:
step 1, placing a metal plate to be processed on a base of a heat treatment device, and clamping and fixing the metal plate by using a blank holder; then, respectively contacting the brush heads of the anode brush and the cathode brush with the edge of the metal plate;
step 2, starting an electric pulse processing device, applying electric pulses to the metal plate by using the electric pulses, and starting timing; when electric pulse is applied to the metal plate, the rolling head of the rolling device also starts to roll the metal plate in a reciprocating manner, and when the metal material reaches the performance corresponding to the heat treatment, the electric pulse and the rolling are stopped;
and 3, cooling the metal plate subjected to rolling treatment to room temperature to obtain a heat-treated metal plate product.
Further, in the step 2, the heating temperature of the electric pulse is 30-650 ℃, the pulse current intensity is 0.1-6000A, the pulse frequency is 10-1000 Hz, and the pulse duty ratio is 10-90%.
Further, the electric pulse and the reciprocating rolling time applied to the metal plate in the step 2 are 8 s-60 min.
Further, the rolling deformation force in the step 2 is within the yield strength of the metal plate.
Compared with the prior art, the invention has the following beneficial effects:
(1) by arranging the electric pulse processing device and the rolling device, when the electric pulse processing device applies high-frequency pulse current to the metal plate, the rolling device drives solute atoms of the metal plate to be enhanced in diffusion capacity under the combined action of thermal motion and pulse electronic impact in a reciprocating rolling mode, so that activation energy is reduced, the tissue quality and performance of the metal plate after heat treatment are improved, and the phase precipitation uniformity is greatly improved.
(2) The cyclic stress generated by the reciprocating rolling drives the solute atoms to diffuse so as to form a large number of fine and uniform atom clusters, vacancies are continuously generated, and the atom clusters can powerfully block dislocation motion so as to achieve a strengthening effect.
(3) The invention improves the utilization rate of the alloy elements, can reduce the addition of the alloy elements on the premise of ensuring the service performance, and achieves the purpose of saving the production cost.
(4) The invention has lower temperature required by heat treatment and shorter heat treatment time, reduces the heat transfer process, reduces the heat dissipation and saves the production cost.
In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to the drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic structural diagram of a reciprocating electric pulse assisted rolling thermal treatment device according to the present invention;
FIG. 2 is a schematic block diagram of the circuit connection of the present invention;
FIG. 3 is a process flow diagram of a reciprocating electric pulse assisted rolling thermal treatment method of the present invention;
the device comprises a power supply 1, an alternating current power supply 2, a controller 3, a machine base 4, a pulse rectifier 5, an anode electric brush 6, a cathode electric brush 7, a blank holder 8, a blank holder slider 9, a blank holder screw 10, a rubber pad 11, a wire clamping holder 12, a wire clamping sleeve 13, a retainer 14, a rolling head support 15, a rolling head 16, an insulating sheath 17, a heat-insulating heat shield and an A-metal plate.
Detailed Description
Embodiments of the invention will be described in detail below with reference to the drawings, but the invention can be implemented in many different ways, which are defined and covered by the claims.
Referring to fig. 1 and 2, an embodiment of the invention provides a reciprocating electric pulse assisted rolling thermal processing apparatus, which includes an ac power supply 1, a controller 2, a machine base 3, a blank pressing apparatus, an electric pulse processing apparatus, and a rolling apparatus. The concrete structure is as follows: the base is provided with a blank pressing device used for pressing a to-be-processed metal plate material A placed on the base, the blank pressing device comprises at least two blank pressing bases 7 arranged at two ends of the base, one side of each blank pressing base, which is close to the metal plate material A, is provided with a blank pressing slide bar 8, a blank pressing screw rod 9 connected with the blank pressing slide bars penetrates through the blank pressing bases, and the blank pressing screw rods are used for controlling the size of pressing force of the blank pressing slide bars on the metal plate material A. The blank holder is provided with a threaded hole, and one end of the blank holder screw is in threaded connection with the threaded hole; an opening communicated with the threaded hole is formed in the bottom of one side, close to the blank, of the edge pressing seat, and one end of the edge pressing rod extends into the opening and is fixedly connected with the lower end of the edge pressing screw rod. When the pressing device is used, the position height of the pressing strip is adjusted by screwing the edge pressing screw rod, so that the purpose of adjusting the pressing force of the pressing strip on the blank A is achieved. The number of the edge pressing bases in the structural arrangement can be specifically set according to the actual size of the blank.
In the preferred embodiment of the present invention, the electric pulse processing device comprises a pulse rectifier 4, an anode brush 5 and a cathode brush 6, and the brush heads of the anode brush and the cathode brush are respectively contacted with the edges of two ends of the metal plate. The controller can control the electric pulse processing device to apply high-frequency pulse current to the metal plate arranged on the machine base so as to heat the metal plate. The rolling device is arranged above the machine base and comprises a retainer 13, a rolling head support 14 and a rolling head 15, wherein the rolling head support is arranged at the bottom of the retainer, and the rolling head is arranged in the rolling head support. The controller can control the feeding motion of the rolling head towards the direction of the metal plate and control the rolling head to roll the metal plate in a reciprocating mode along the length direction of the metal plate. In the structure, the rolling head feeds (moves towards the direction of a metal plate), the feeding can be divided into multiple times or single time, the feeding amount/speed of each time is determined by the parameters of the material, the deformation of the metal plate in the thickness direction is within the yield strength of the material, then the rolling head reciprocates along the length direction, and the reciprocating speed and the reciprocating times are determined by the properties of the material.
In the preferred embodiment of the present invention, two ends of the machine base are respectively provided with a wire clamping seat 11, and a wire clamping sleeve 12 is arranged on the wire clamping seat; the wire clamping seat and the wire clamping sleeve are made of plastic materials. Furthermore, the outer layer of the line penetrating through the wire clamping sleeve is wrapped with an insulating sheath 16, so that the service life of the line can be effectively prolonged. Meanwhile, in order to prevent the surface of the metal plate from being damaged, rubber pads 10 are arranged on the top surface of the base and the parts of the edge pressing sliding strips, which are used for being in contact with the metal plate, respectively.
In the preferred embodiment of the present invention, the heat treatment apparatus further comprises a heat insulation cover 17 covering the exterior of the heat treatment apparatus, so as to effectively prevent heat dissipation and further reduce the production cost.
Referring to fig. 3, the present invention further provides a reciprocating electric pulse assisted rolling thermal processing method, which comprises the following steps:
step 1, placing a metal plate material A to be processed on a machine base 3 of a heat treatment device, and clamping and fixing the metal plate material by using a side pressing device, namely, driving a side pressing slide bar to tightly press the edge of the metal plate material by screwing a side pressing screw rod to realize clamping and fixing of the metal plate material. Next, brush heads of the anode brush 5 and the cathode brush 6 are respectively brought into contact with the edge of the metal plate material a.
Step 2, starting an electric pulse processing device, applying electric pulses to the metal plate by using the electric pulses, and starting timing; when electric pulse is applied to the metal plate, the rolling head 15 of the rolling device also starts to roll the metal plate in a reciprocating manner, and the electric pulse and the rolling are stopped when the metal material reaches the performance corresponding to the heat treatment; wherein the target temperature is 30-650 ℃, the pulse current intensity is 0.1-6000A, the pulse frequency is 10-1000 Hz, and the pulse duty ratio is 10-90%; the rolling deformation force is within the yield strength of the metal plate.
And 3, cooling the rolled metal plate to room temperature to obtain the heat-treated metal plate.
In the embodiment of the present invention, the pulse duration and the rolling duration of the blank may be set according to the effect to be achieved by the heat treatment. The cooling mode of the rolled metal plate can be determined according to the requirements of users, and the cooling mode comprises water cooling, air cooling, oil cooling and the like.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. The reciprocating type electric pulse auxiliary rolling heat treatment device is characterized by comprising an alternating current power supply (1), a controller (2), a base (3), a blank pressing device, an electric pulse treatment device and a rolling device, wherein the blank pressing device is arranged on the base and is used for pressing a metal plate (A) to be treated on the base; the electric pulse processing device comprises a pulse rectifier (4), an anode electric brush (5) and a cathode electric brush (6), wherein electric brush heads of the anode electric brush and the cathode electric brush are respectively used for contacting with two ends of the metal plate; the alternating current power supply is connected with the controller, the controller is respectively connected with the rolling device and the pulse rectifier, and the pulse rectifier is respectively connected with the anode electric brush and the cathode electric brush; the rolling device is arranged above the base and used for performing reciprocating rolling on a metal plate (A) arranged on the base.
2. The heat treatment device according to claim 1, wherein the edge pressing device comprises at least two edge pressing bases (7) arranged at two ends of the base, one edge pressing slide (8) is arranged on one side of each edge pressing base close to the metal plate (A), an edge pressing screw (9) connected with the edge pressing slide penetrates through the edge pressing bases, and the edge pressing screw is used for controlling the pressing force of the edge pressing slides on the metal plate.
3. The heat treatment device according to claim 2, wherein an opening is formed in the bottom of one side, close to the metal plate, of the blank holder, and one end of the blank holder slide bar extends into the opening and is fixedly connected with the lower end of the blank holder screw rod.
4. Heat treatment installation according to claim 2, characterised in that the machine base and the portions of the edge-pressing slider intended to come into contact with the sheet metal are provided with rubber pads (10).
5. The heat treatment device according to claim 1, wherein the machine base is further provided with a wire clamping seat (11) at each of two ends thereof, and a wire clamping sleeve (12) is arranged on the wire clamping seat.
6. The heat treatment device according to claim 1, characterized in that the rolling device comprises a cage (13), a rolling head support (14) arranged at the cage bottom and a rolling head (15) arranged within the rolling head support.
7. A reciprocating electric pulse assisted rolling heat treatment method based on the heat treatment device of any one of claims 1 to 6, characterized by comprising the following steps:
step 1, placing a metal plate material (A) to be treated on a machine base (3) of a heat treatment device, and clamping and fixing the metal plate material by using a blank holder; then, electric brush heads of the anode electric brush (5) and the cathode electric brush (6) are respectively contacted with the edge of the metal plate material (A);
step 2, starting an electric pulse processing device, applying electric pulses to the metal plate by using the electric pulses, and starting timing; when electric pulse is applied to the metal plate, a rolling head (15) of a rolling device starts to perform reciprocating rolling on the metal plate, and when the metal material reaches the performance corresponding to the heat treatment of the metal material, the electric pulse and the rolling are stopped;
and 3, cooling the metal plate subjected to rolling treatment to room temperature to obtain a heat-treated metal plate product.
8. The heat treatment method according to claim 7, wherein the heating temperature of the electric pulse in the step 2 is 30 to 650 ℃, the pulse current intensity is 0.1 to 6000A, the pulse frequency is 10 to 1000Hz, and the pulse duty ratio is 10 to 90%.
9. Heat treatment process according to claim 7, characterised in that the electric pulses and the reciprocal rolling time applied to the sheet metal material (A) of step 2 are comprised between 8s and 60 min.
10. The heat treatment method according to claim 7, wherein the rolling deformation force in the step 2 is within the yield strength of the sheet metal material.
CN202011222807.1A 2020-11-05 2020-11-05 Reciprocating electric pulse auxiliary rolling heat treatment device and method Pending CN112481456A (en)

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Application Number Priority Date Filing Date Title
CN202011222807.1A CN112481456A (en) 2020-11-05 2020-11-05 Reciprocating electric pulse auxiliary rolling heat treatment device and method

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114515937A (en) * 2022-03-17 2022-05-20 浙江工业大学 Electric pulse auxiliary rolling processing platform

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108406224A (en) * 2018-01-31 2018-08-17 华南理工大学 A kind of high-frequency direct-current heating auxiliary roll processing device and its processing method
CN109158829A (en) * 2018-07-31 2019-01-08 清华大学深圳研究生院 A kind of metal component optimization method and molding equipment based on increasing material technological forming

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108406224A (en) * 2018-01-31 2018-08-17 华南理工大学 A kind of high-frequency direct-current heating auxiliary roll processing device and its processing method
CN109158829A (en) * 2018-07-31 2019-01-08 清华大学深圳研究生院 A kind of metal component optimization method and molding equipment based on increasing material technological forming

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114515937A (en) * 2022-03-17 2022-05-20 浙江工业大学 Electric pulse auxiliary rolling processing platform

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