CN103406415A - Current-assisted rapid hot forming device and method for long and thin high-strength-steel structural components - Google Patents
Current-assisted rapid hot forming device and method for long and thin high-strength-steel structural components Download PDFInfo
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- CN103406415A CN103406415A CN2013103703288A CN201310370328A CN103406415A CN 103406415 A CN103406415 A CN 103406415A CN 2013103703288 A CN2013103703288 A CN 2013103703288A CN 201310370328 A CN201310370328 A CN 201310370328A CN 103406415 A CN103406415 A CN 103406415A
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Abstract
The invention discloses a current-assisted rapid hot forming device and method for long and thin high-strength-steel structural components, relates to the technical field of high-strength-steel hot forming, particularly relates to a current-assisted self-resistance heating forming device and method and solves the problems that existing rapid hot forming devices are complicated to energize and existing rapid hot forming methods are applied to materials of low melting points and low hardness. The device comprises a power supply, a die, a pair of sheet clamping electrodes, two cushion blocks and two insulating mica sheets, the power supply, the sheet clamping electrodes and a sheet to be formed form an energized loop, the sheet clamping electrodes and the rest part of the die are insulated, insulation is achieved through the high-temperature-resistant insulating mica sheets, and the sheet to be formed is not in contact with the die. The method comprises that joule resistance heat produced by a current passing the sheet is used for heating the sheet directly, and after the forming temperature is reached, the rapid in-situ stamping forming is conducted. The device and the method are used for manufacturing the high-strength-steel structural components for vehicles.
Description
Technical field
The present invention relates to high-strength steel hot forming technical field, particularly a kind of electric current auxiliary from resistance heating shaping device and method.
Background technology
Along with the development of auto industry, the series of problems such as energy shortage and environmental pollution become increasingly conspicuous in recent years, vehicle body loss of weight and the energy-saving and cost-reducing common choice that becomes the main flow automobile industry.The high-strength steel material has obtained increasing application with its remarkable effect of bringing into play in the vehicle body loss of weight in automobile industry.But the plastic deformation scope of high-strength steel is very little at normal temperatures, and required plastic force is large, the rear resilience that is shaped is serious, easy to crack, and very serious to the infringement of mould, and forming property is very poor.Traditional cold punching forming process can not meet its forming requirements, must adopt the hot forming technology.
At present, the hot forming technology mainly contains two kinds: a kind of is the shaping plate to be put into to heating furnace heat, to be heated after forming temperature, and plate is transported on former from heating furnace.Plate under condition of high temperature radiating rate in transfer process is fast, serious heat loss, and very serious surface oxidation phenomenon can occur.The loss of temperature and material makes the sheet forming temperature can't reach desired temperature and the shaping rear surface is second-rate.Another kind of mode is plate and mould to be put into to heating furnace together heat, and because plate and mold integral heat, most heats have been delivered on mould, and capacity usage ratio is very low.In addition, the mode that mould and plate are accepted heat is mainly to conduct and heat radiation by heat, and the transmission speed of heat is slow, being heated to forming temperature needs the time longer, and forming process needs long time, and energy consumption is large, and the mould loss is fast, production efficiency is very low.For example application number is 201010205200.2, " electric current is from hindering hot briquetting aluminum base composite material thin wall part method " by name, a joule resistance heat that blank produces directly heats blank itself to utilize electric current to flow through, the utilization rate of energy and the efficiency of heating have greatly been improved, but the applied device of the method that this patent provides powers up complexity, and it is low to be applied in fusing point, the aluminum matrix composite that hardness is low.
Summary of the invention
The present invention is in order to solve the complexity that powers up of existing Rapid Thermal building mortion, and existing Rapid Thermal manufacturing process can not be applied to the problem of the material that fusing point is high, hardness is high, proposed the auxiliary Rapid Thermal building mortion of high-strength steel slim-lined construction spare electric current and method.
High-strength steel slim-lined construction spare electric current is assisted the Rapid Thermal building mortion, and it comprises power supply, mould, a pair of plate holding electrode, two cushion blocks and two insulating concrete mica plates,
Described mould is comprised of mold and bed die,
Two cushion blocks lay respectively at the both sides of bed die, at a cushion block, are fixedly connected with by an insulating concrete mica plate with a plate holding electrode,
Mold be positioned at plate to be formed directly over, bed die be positioned at plate to be formed under, the shaping of plate to be formed is placed in the cavity of bed die, the plate holding electrode is for clamping plate to be formed, and two electrode tips of plate holding electrode are connected on power supply by copper braid over braid wire.
Adopt the auxiliary Rapid Thermal building mortion of high-strength steel slim-lined construction spare electric current to realize quick hot formed method, first assist the Rapid Thermal building mortion on hydraulic press in high-strength steel slim-lined construction spare electric current, described method is:
Step a: according to cross sectional dimensions and the resistance data of plate to be formed, select forming parameters;
Step b: plate to be formed is placed between mold and bed die, and the shaping of plate to be formed is placed in the cavity of bed die, the plate two ends clamped with the plate holding electrode, and then energising heating, firing rate is 5 ℃/s～20 ℃/s;
Step c: measure in real time the temperature of plate to be formed by infrared radiation thermometer, and adjust in real time the output current parameter of power supply (1) according to its temperature;
Steps d: after temperature reaches 700 ℃～800 ℃, by hydraulic press, exert pressure, the patrix pressurized is descending, the patrix pressure head is pressed into plate in the counterdie die cavity, make plate generation plastic deformation to be formed, make plate to be formed and the laminating of bed die inner surface, thereby complete the auxiliary Rapid Thermal forming process of high-strength steel slim-lined construction spare electric current one time.
The present invention utilizes electric current directly plate to be heated by the joule resistance heat that plate produces, reach after forming temperature and carry out that original position is stamping fast, this technology not only can avoid monoblock type in traditional superplasticforming technique to add the thermal loss of heat loss on other parts such as mould, and make that heating process is very fast, the slab interior Temperature Distribution is very even, greatly improved the utilization rate of energy and the efficiency of heating.In addition, because plate can form immediately after temperature, temperature is even, is conducive to the plastic deformation of plate, improves product quality.
The present invention applies a pair of plate holding electrode, it is firmly convenient that adding of plate held, and two electrode tips that directly power supply are added in to a pair of plate holding electrode get final product, power up conveniently, and the method for the invention temperature is added to 1000 ℃ of left and right, can be applicable to fusing point higher, the plate that hardness is larger, as high-strength steel.
The accompanying drawing explanation
Fig. 1 is the structure chart of the auxiliary Rapid Thermal building mortion of the described high-strength steel slim-lined construction spare of the specific embodiment one electric current;
The tomograph of the auxiliary Rapid Thermal building mortion of the described high-strength steel slim-lined construction spare of Fig. 2 specific embodiment one electric current;
Fig. 3 is the flow chart of the auxiliary Rapid Thermal manufacturing process of the described high-strength steel slim-lined construction spare of the specific embodiment four electric current.
The specific embodiment
The specific embodiment one: present embodiment is described referring to Fig. 1 and Fig. 2, the described high-strength steel of present embodiment slim-lined construction spare electric current is assisted the Rapid Thermal building mortion, it comprises power supply 1, mould, a pair of plate holding electrode 3, two cushion blocks 4 and two insulating concrete mica plates 5
Described mould is comprised of mold 2-1 and bed die 2-2,
Two cushion blocks 4 lay respectively at the both sides of bed die 2-2, at a cushion block 4, are fixedly connected with by an insulating concrete mica plate 5 with a plate holding electrode 3,
Mold 2-1 be positioned at plate 6 to be formed directly over, bed die 2-2 be positioned at plate 6 to be formed under, the shaping of plate 6 to be formed is placed in the cavity of bed die, plate holding electrode 3 is be used to clamping plate to be formed, and two electrode tips of plate holding electrode 3 are connected on power supply 1 by copper braid over braid wire.
Described bed die 2-2 is provided with a groove, and mold 2-1 is provided with a projection, and this groove that is raised in bed die 2-2 adapts.
The described power supply 1 of present embodiment, plate holding electrode 3 and plate to be formed form power circuit.Plate holding electrode 3 keeps insulation with the remainder of mould, and insulation is passed through resistant to elevated temperatures insulating concrete mica plate 5 and realized, plate to be formed does not contact with mould, and insulating Design makes mould can not shunt the electric current of the plate to be formed of flowing through, and reduces energy loss.The resistance of plate to be formed will be far longer than the resistance of loop other parts in described loop, so electric current can produce a large amount of Joule heats on plate to be formed, can be at short notice (tens seconds to hundreds of second) be heated to the hot forming temperature.
The specific embodiment two: this implementation method is the further restriction to the specific embodiment one, and it also comprises infrared radiation thermometer, and described infrared radiation thermometer is for measuring in real time the temperature of plate 6 to be formed.
The specific embodiment three: this implementation method is the further restriction to the specific embodiment one, the holder of described plate holding electrode 3 for adopting two copper coins to form.
The specific embodiment four: this implementation method is the further restriction to the specific embodiment one, the output LOW voltage scope of described power supply 1: 2V～6V, output current scope: 500A～1500A.
The specific embodiment five: present embodiment is described referring to Fig. 3, adopt the auxiliary Rapid Thermal building mortion of the described high-strength steel slim-lined construction spare of the specific embodiment two electric current to realize quick hot formed method, first assist the Rapid Thermal building mortion on hydraulic press in high-strength steel slim-lined construction spare electric current, described method is:
Step a: according to cross sectional dimensions and the resistance data of plate to be formed, select forming parameters;
Step b: plate 6 to be formed is placed between mold 2-1 and bed die 2-2, and the shaping of plate 6 to be formed is placed in the cavity of bed die, the plate two ends clamped with plate holding electrode 3, and then energising heating, firing rate is 5 ℃/s～20 ℃/s;
Step c: measure in real time the temperature of plate 6 to be formed by infrared radiation thermometer, and adjust in real time the output current parameter of power supply 1 according to its temperature;
Steps d: after temperature reaches 700 ℃～800 ℃, by hydraulic press, exert pressure, the patrix pressurized is descending, the patrix pressure head is pressed into plate in the counterdie die cavity, make plate generation plastic deformation to be formed, make plate to be formed and the laminating of bed die inner surface, thereby complete the auxiliary Rapid Thermal forming process of high-strength steel slim-lined construction spare electric current one time.
The die sinking pickup, school shape, trimming, obtain final part.
The described forming parameters of present embodiment comprises and is mainly electric current, and the method for selection is the technological means that those skilled in the art have,
Described plastic deformation comprises the deformation stages such as bending, pull and stretch and subsides mould,
The output current parameter of the described real-time adjustment power supply 1 of step c is a kind of technological means known in those skilled in the art.
The present invention proposes electric current auxiliary heat shaping scheme.By on plate, applying certain electric current, make plate from the resistance heating, meet the requirements of temperature, and then the original position shaping, improve forming quality.This technique can reduce bending springback and the hardening phenomenon in punching course effectively, improves the Sheet Metal Forming Technology performance of sheet material, has saved simultaneously the energy, has reduced the oxidation in the generative process.By electric current auxiliary heat forming experiment, obtain formation of parts, the formation of parts surface quality is better, and thickness distribution is even, and without obvious cracking phenomena, geometry and the dimensional accuracy of part are better, have reached the expection forming effect.Many groups high-strength steel plate is formed to experiment, and it is better that mould repeats the processing effect, and the surface abrasion situation improves.
Claims (5)
1. the auxiliary Rapid Thermal building mortion of high-strength steel slim-lined construction spare electric current, is characterized in that, it comprises power supply (1), mould, a pair of plate holding electrode (3), two cushion blocks (4) and two insulating concrete mica plates (5),
Described mould is comprised of mold (2-1) and bed die (2-2),
Two cushion blocks (4) lay respectively at the both sides of bed die (2-2), at a cushion block (4), are fixedly connected with by an insulating concrete mica plate (5) with a plate holding electrode (3),
Mold (2-1) be positioned at plate to be formed (6) directly over, bed die (2-2) be positioned at plate to be formed (6) under, the shaping of plate to be formed (6) is placed in the cavity of bed die, plate holding electrode (3) is be used to clamping plate to be formed, and two electrode tips of plate holding electrode (3) are connected on power supply (1) by copper braid over braid wire.
2. the auxiliary Rapid Thermal building mortion of high-strength steel slim-lined construction spare electric current according to claim 1, is characterized in that, it also comprises infrared radiation thermometer, and described infrared radiation thermometer is for measuring in real time the temperature of plate to be formed (6).
3. the auxiliary Rapid Thermal building mortion of high-strength steel slim-lined construction spare electric current according to claim 1, is characterized in that, the holder of described plate holding electrode (3) for adopting two copper coins to form.
4. the auxiliary Rapid Thermal building mortion of high-strength steel slim-lined construction spare electric current according to claim 1, is characterized in that the output LOW voltage scope of described power supply (1): 2V～6V, output current scope: 500A～1500A.
5. adopt the auxiliary Rapid Thermal building mortion of high-strength steel slim-lined construction spare electric current claimed in claim 2 to realize quick hot formed method, first assist the Rapid Thermal building mortion on hydraulic press in high-strength steel slim-lined construction spare electric current, described method is:
Step a: according to cross sectional dimensions and the resistance data of plate to be formed, select forming parameters;
Step b: plate to be formed (6) is placed between mold (2-1) and bed die (2-2), the shaping of plate to be formed (6) is placed in the cavity of bed die, the plate two ends are clamped with plate holding electrodes (3), then energising heating, firing rate is 5 ℃/s～20 ℃/s;
Step c: measure in real time the temperature of plate to be formed (6) by infrared radiation thermometer, and adjust in real time the output current parameter of power supply (1) according to its temperature;
Steps d: after temperature reaches 700 ℃～800 ℃, by hydraulic press, exert pressure, the patrix pressurized is descending, the patrix pressure head is pressed into plate in the counterdie die cavity, make plate generation plastic deformation to be formed, make plate to be formed and the laminating of bed die inner surface, thereby complete the auxiliary Rapid Thermal forming process of high-strength steel slim-lined construction spare electric current one time.
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104028603A (en) * | 2014-05-29 | 2014-09-10 | 哈尔滨理工大学 | Heterogeneous material tailor-welded blank hot stamping forming device and method with controllable temperature field |
| CN104475587A (en) * | 2014-11-12 | 2015-04-01 | 华中科技大学 | Conduction heating forming device and method |
| CN104588521A (en) * | 2014-12-19 | 2015-05-06 | 北京卫星制造厂 | Current auxiliary heat forming device and method with flexible clamping adopted |
| CN107913930A (en) * | 2017-11-04 | 2018-04-17 | 北华航天工业学院 | It is a kind of to heat press-processing method from resistance for difficult deformable metal plate |
| CN109382448A (en) * | 2017-08-03 | 2019-02-26 | 中国商用飞机有限责任公司 | A kind of self-heating manufacturing process that profile pressure is sunken |
| CN109940080A (en) * | 2019-04-04 | 2019-06-28 | 南京航空航天大学 | From resistance electric heating plate drawing and forming device and method |
| CN110434555A (en) * | 2019-06-22 | 2019-11-12 | 哈尔滨工业大学（威海） | A kind of method of sheet metal hollow structural members electric current assist formation |
| CN110479806A (en) * | 2019-08-22 | 2019-11-22 | 北华航天工业学院 | A kind of metal elongate articles are from resistance heating stamping device |
| CN111957777A (en) * | 2020-08-05 | 2020-11-20 | 合肥工业大学 | Electric auxiliary bending forming process method for high-temperature titanium alloy grid rib wallboard |
| CN113600693A (en) * | 2021-07-29 | 2021-11-05 | 许聪 | Hot stamping hardware mould |
| CN115430755A (en) * | 2022-11-07 | 2022-12-06 | 中国航发沈阳黎明航空发动机有限责任公司 | Built-in electrode hot forming device and method based on optimized blank shape |
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104028603A (en) * | 2014-05-29 | 2014-09-10 | 哈尔滨理工大学 | Heterogeneous material tailor-welded blank hot stamping forming device and method with controllable temperature field |
| CN104475587A (en) * | 2014-11-12 | 2015-04-01 | 华中科技大学 | Conduction heating forming device and method |
| CN104588521A (en) * | 2014-12-19 | 2015-05-06 | 北京卫星制造厂 | Current auxiliary heat forming device and method with flexible clamping adopted |
| CN104588521B (en) * | 2014-12-19 | 2017-04-19 | 北京卫星制造厂 | Current auxiliary heat forming device and method with flexible clamping adopted |
| CN109382448A (en) * | 2017-08-03 | 2019-02-26 | 中国商用飞机有限责任公司 | A kind of self-heating manufacturing process that profile pressure is sunken |
| CN107913930A (en) * | 2017-11-04 | 2018-04-17 | 北华航天工业学院 | It is a kind of to heat press-processing method from resistance for difficult deformable metal plate |
| CN109940080A (en) * | 2019-04-04 | 2019-06-28 | 南京航空航天大学 | From resistance electric heating plate drawing and forming device and method |
| CN110434555A (en) * | 2019-06-22 | 2019-11-12 | 哈尔滨工业大学（威海） | A kind of method of sheet metal hollow structural members electric current assist formation |
| CN110479806A (en) * | 2019-08-22 | 2019-11-22 | 北华航天工业学院 | A kind of metal elongate articles are from resistance heating stamping device |
| CN110479806B (en) * | 2019-08-22 | 2020-11-27 | 北华航天工业学院 | Self-resistance heating stamping device for metal elongated parts |
| CN111957777A (en) * | 2020-08-05 | 2020-11-20 | 合肥工业大学 | Electric auxiliary bending forming process method for high-temperature titanium alloy grid rib wallboard |
| CN113600693A (en) * | 2021-07-29 | 2021-11-05 | 许聪 | Hot stamping hardware mould |
| CN113600693B (en) * | 2021-07-29 | 2023-08-11 | 深圳市伟胜达五金有限公司 | Hot stamping hardware die |
| CN115430755A (en) * | 2022-11-07 | 2022-12-06 | 中国航发沈阳黎明航空发动机有限责任公司 | Built-in electrode hot forming device and method based on optimized blank shape |
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