CN102896220A - Hot forming/hot sizing/heat treatment integrated forming method and die - Google Patents
Hot forming/hot sizing/heat treatment integrated forming method and die Download PDFInfo
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- CN102896220A CN102896220A CN2012103665953A CN201210366595A CN102896220A CN 102896220 A CN102896220 A CN 102896220A CN 2012103665953 A CN2012103665953 A CN 2012103665953A CN 201210366595 A CN201210366595 A CN 201210366595A CN 102896220 A CN102896220 A CN 102896220A
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Abstract
The invention belongs to the field of precision sheet metal processing, and relates to a hot forming/hot sizing/heat treatment integrated forming method and a die, for the purpose of fitting the precision forming of high-temperature and high-strength plates such as high-temperature titanium alloys and titanium-aluminum intermetallic compound thin-wall revolving parts for aerospace. The die comprises a concave die, a mandrel, a tray and a draw bar, wherein the inner wall of the concave die is a cylindrical or conical surface, the shape of the mandrel is matched with that of the inner wall of the concave die, the tray is arranged at the bottom of the concave die, and the draw bar is connected with the tray. The method comprises the steps of blanking, circle making, hot sizing, longitudinal seam welding, hot forming, and heat treatment. According to the invention, the processing forming of conic cylindrical parts made of difficultly-deformed materials for aerospace is effectively guaranteed, and the technical problem of carrying out precision manufacturing on the difficultly-deformed materials is solved.
Description
Technical field
The invention belongs to accurate panel beating field, relate to a kind of hot forming/hot school shape/heat treatment integral forming method and mould, it is applicable to Aero-Space with the precision form of high strength at high temperature sheet material such as high-temperature titanium alloy, Intermatallic Ti-Al compound thin-walled rotary part.
Background technology
The speed of aerospace flight vehicle flight is more and more faster, requires key position more heat-resisting, therefore more and more adopts the high-temperature-resistant structure material, such as titanium alloy, high-temperature titanium alloy, titanium aluminum based metal compound etc.This class materials'use temperature is high, elevated temperature strength is large, its sheet moulding technical difficulty is large, resilience is serious after adopting conventional metal plate punching to be shaped, tearing tendency is large, generally needs to adopt thermal processing method, but because such material property extremely is sensitive to heat engine tool and Technology for Heating Processing, its complex component is very difficult such as the part processing with flange, generally need multiple working procedure, many molds, processing cost is higher, and efficient is lower.
Summary of the invention
The objective of the invention is provides a kind of hot forming/hot school shape/heat treatment integral forming method and mould in order to be fit to the precision form of Aero-Space usefulness high strength at high temperature sheet material such as high-temperature titanium alloy, Intermatallic Ti-Al compound thin-walled rotary part.
The technical solution adopted in the present invention is:
A kind of hot forming/hot school shape/heat treatment integral forming mould comprises that inwall is the die of cylinder or taper seat, the core that matches with the die inner wall shape, the pallet that is positioned at the die bottom and the pull bar that links to each other with pallet.
Aforesaid a kind of hot forming/hot school shape/heat treatment integral forming mould, wherein: be equipped with the patrix for parts flanged-edge at the die top.
Aforesaid a kind of hot forming/hot school shape/heat treatment integral forming mould, wherein: be provided with the boss that matches with pallet in the die bottom.
A kind of hot forming/hot school shape/heat treatment integral forming method comprises the steps:
Step S1: blanking;
Step S2: circle circle;
Step S3: hot school shape; Part to be processed behind the circle circle is put into mould; Mould and part to be processed 6 integral body are put into heating furnace heating and insulation a period of time; Take out part to be processed, obtain the part to be processed with stable circularity;
Step S4: the part to be processed that will take out welds;
Step S5: hot forming; Part to be processed after the welding is put into mould; Mould and part integral body to be processed are put into heating furnace heating and insulation a period of time; Take out part to be processed, obtain to have the part to be processed at flange position;
Step S6: heat treatment, release pressure after the hot forming.
Aforesaid a kind of hot forming/hot school shape/heat treatment integral forming method, wherein: in the shape of the hot school of described step S3, part to be processed is put into die, then put into core compacting part to be processed; Mould and part integral body to be processed are put into heating furnace heating and insulation a period of time; Take out core, part to be processed;
Aforesaid a kind of hot forming/hot school shape/heat treatment integral forming method, wherein: in the described step S5 hot forming: first pull bar and pallet are put into die, and pallet is fixed on the boss of die bottom; Then the part to be processed after the welding is put into die, put into core and rely on its deadweight to make it to fit with part to be processed and die; Be heated to the patrix that closes after temperature required, patrix is exerted pressure and pressurize a period of time be shaped Flange of part; Remove patrix after the shaping), pull bar is sling, thereby pallet and part to be processed are taken out.
The invention has the beneficial effects as follows:
The method adopts blank circle circle → hot school shape → weldering longitudinal joint → hot forming → heat-treating methods and mould, guaranteed that effectively Aero-Space with the shaping of difficult-to-deformation material conical barrel shape piece, have solved the Precision Manufacturing Technology difficult problem of such difficult-to-deformation material;
The method can only realize having saved hot procedure with the integral forming of the complex structural member of flange with a mold, and die cost is low, and the product working (machining) efficiency is high.
Obtain stable cone barrel blank, the assembly difficulty when having reduced the difficult-to-deformation material longitudinal seam welding by hot school shape;
Hot forming and heat treatment are integrated in Thermal Cycling, have greatly improved working (machining) efficiency, reduced production cost.
Description of drawings
Fig. 1 is a kind of hot forming provided by the invention/hot school shape/heat treatment integral forming mould structure and part assembly drawing to be processed;
Fig. 2 is the cone barrel part drawing with flange;
Fig. 3 is blank and development size figure thereof;
Among the figure, 1, die, 2, core, 3, patrix, 4, pull bar, 5, pallet, 6, part to be processed.
The specific embodiment
Below in conjunction with drawings and Examples a kind of hot forming provided by the invention/hot school shape/heat treatment integral forming method and mould are introduced:
As shown in Figure 1, a kind of hot forming/hot school shape/heat treatment integral forming mould comprises that inwall is the die 1 of cylinder or taper seat, core 2, the pallet 5 that is positioned at die 1 bottom that matches with die 1 inner wall shape and the pull bar 4 that links to each other with pallet 5.
In order to be made as the flange of part, be equipped with the patrix 3 for parts flanged-edge at die 1 top.
For pallet 5 being positioned at die 1 bottom, be provided with the boss that matches with pallet 5 in die 1 bottom.
Use this mould to be, at first pull bar 4 and pallet 5 are put into die 1, and pallet 5 is fixed on the die 1 bottom boss; Then the part to be processed 6 of the pre-circle circle of warp is put into die 1, and part to be processed 6 bases are fallen within on the pallet 5; Put into again core 2, rely on core 2 deadweights that itself and part to be processed 6 and die 1 are fitted tightly; Be heated to the patrix 3 that closes after temperature required, patrix 3 is exerted pressure and pressurize be shaped the Flange of part; Remove patrix 3 after the shaping, pull bar 4 is sling, thereby part after pallet 5 and the processing is taken out.
A kind of hot forming/hot school shape/heat treatment integral forming method comprises the steps:
Step S1: blanking;
Step S2: circle circle;
Step S3: hot school shape; Part to be processed 6 behind the circle circle is put into mould; Mould and part to be processed 6 integral body are put into heating furnace heating and insulation a period of time; Take out part 6 to be processed, obtain the part to be processed 6 with stable circularity;
Step S4: the part to be processed 6 that will take out welds;
Step S5: hot forming; Part to be processed 6 after the welding is put into mould; Mould and part to be processed 6 integral body are put into heating furnace heating and insulation a period of time; Take out part 6 to be processed, obtain to have the part to be processed 6 at flange position;
Step S6: heat treatment, release pressure after the hot forming.
For obtaining better effect, can carry out following optimization to above steps and select:
Step S1 blanking: calculate the development size of thin-walled rotary part, adopt single-piece blank under laser cutting or the water cutting method, remove the otch burr.
For example take with the cone barrel part of flange as example, its geomery as shown in Figure 1, material is the thick Ti of 1.0mm
2The AlNb intermetallic compound; Then calculate the development size of thin-wall special-shaped sealing part, size adopts single-piece blank under the numerical control water cutting method as shown in Figure 2, removes the otch burr.
Step S2 encloses circle: adopt general circle circular knitting machine that sheet material is carried out preform, enclose into the blank with preliminary cone barrel shape or arc, substantially can't enclose into standard cone barrier part because such high temperature resistant sheet material cold forming resilience is large this moment; Can only tentatively enclose into the semicircle arcuation.
The hot school of step S3 shape: with putting into die 1 behind the part 6 surface brushing high temp. protective coatings to be processed, then put into core 2 compactings part 6 to be processed; Mould and part to be processed 6 integral body are put into heating furnace heating and insulation a period of time; Take out core 2, part to be processed 6, obtain the cone barrel blank with stable circularity;
The optional high temp. protective coating Ti-1# that is coated with for example, mold integral put into heating furnace and are heated to 900 ℃ and be incubated 2h.This step need not used patrix 3, pull bar 4, pallet 5, only needing to enclose in advance round part to be processed 6 packs in the die 1, put into core 2 and rely on its deadweight to make it to fit tightly with part 6 to be processed and die 1, take out the cone barrel blank that core 2 and part to be processed 6 can obtain to have stable circularity behind the heat tracing.
Step S4 welding: welding cone cylinder blank longitudinal joint, the conical barrel shape piece of acquisition sealing.
Can take following preferred version during welding: for example can to the cone cylinder blank pickling of acquisition before weldering, clean up and be placed on 100～150 ℃ of lower oven dry 20～30 minutes in the drying oven; Adopt wire brush and scraper to be polished in the weld zone, remove burr, and use the acetone scrub, keep the weld zone cleaning before the weldering; Workpiece is assemblied on the General clamping to compress longitudinal joint is overlapped with the welding gun run trace; Starting protection gas is evenly put solid 4～6 points according to the assembling situation on longitudinal joint, the laser weld longitudinal joint guarantees that appearance of weld is good.
Step S5 hot forming: again put into die 1 after high temp. protective coating is brushed on part to be processed 6 surfaces after will welding, put into core 2 compactings, mould and part to be processed 6 integral body are put into heating furnace heating and insulation a period of time, patrix 3 is exerted pressure and pressurize the flange position of the cone cylinder that is shaped;
Preferably, can will again put into mould behind the conical barrel shape piece surface brushing high temp. protective coating Ti-1#.First pull bar 4 and pallet 5 are put into die 1, and pallet 5 is fixed on the die 1 bottom boss; Then the part to be processed 6 after the welding is put into die 1, put into core 2 and rely on its deadweight to make it to fit tightly with part 6 to be processed and die 1; The patrix 3 that closes after being heated to temperature required 850 ℃ is exerted pressure and pressurize 5min be shaped the Flange of part to patrix 3; Remove patrix 3 after the shaping, pull bar 4 is sling, thereby pallet 5 and part to be processed 6 are taken out.
Step S6 heat treatment: release pressure after the hot forming, continuation is placed on part and mould in the heating furnace and is incubated, temperature retention time is determined according to the heat treating regime of material, takes out successively patrix 3, core 2 and part after the insulation, can obtain the cone barrel part with Flange.
Can be preferred, after hot forming, lift patrix 3 release pressures, continue part and mould be positioned in the heating furnace and under 850 ℃ of temperature conditions, be incubated 2h, take out successively patrix, core and part after the insulation.
Claims (6)
1. hot forming/hot school shape/heat treatment integral forming mould is characterized in that: comprise that inwall is the die (1) of cylinder or taper seat, the core (2), the pallet (5) that is positioned at die (1) bottom and the pull bar (4) that links to each other with pallet (5) that match with die (1) inner wall shape.
2. a kind of hot forming according to claim 1/hot school shape/heat treatment integral forming mould is characterized in that: be equipped with the patrix (3) for parts flanged-edge at die (1) top.
3. a kind of hot forming according to claim 2/hot school shape/heat treatment integral forming mould is characterized in that: be provided with the boss that matches with pallet (5) in die (1) bottom.
4. a kind of hot forming according to claim 3/hot school shape/heat treatment integral forming method comprises the steps:
Step S1: blanking;
Step S2: circle circle;
Step S3: hot school shape; Part to be processed (6) behind the circle circle is put into mould; Mould and part to be processed 6 integral body are put into heating furnace heating and insulation a period of time; Take out part to be processed (6), obtain the part to be processed (6) with stable circularity;
Step S4: the part to be processed (6) that will take out welds;
Step S5: hot forming; Part to be processed (6) after the welding is put into mould; Mould and part to be processed (6) integral body are put into heating furnace heating and insulation a period of time; Take out part to be processed (6), obtain to have the part to be processed (6) at flange position;
Step S6: heat treatment, release pressure after the hot forming.
5. a kind of hot forming according to claim 4/hot school shape/heat treatment integral forming method, it is characterized in that: in the shape of the hot school of described step S3, part to be processed (6) is put into die (1), then put into core (2) compacting part to be processed (6); Mould and part to be processed (6) integral body are put into heating furnace heating and insulation a period of time; Take out core (2), part to be processed (6).
6. a kind of hot forming according to claim 5/hot school shape/heat treatment integral forming method, it is characterized in that: in the described step S5 hot forming: first pull bar (4) and pallet (5) are put into die (1), and pallet (5) is fixed on the boss of die (1) bottom; Then the part to be processed (6) after the welding is put into die (1), put into core (2) and rely on its deadweight to make it to fit with part to be processed (6) and die (1); Be heated to the patrix (3) that closes after temperature required, patrix (3) is exerted pressure and pressurize a period of time be shaped Flange of part; Remove patrix (3) after the shaping, pull bar (4) is sling, thereby pallet (5) and part to be processed (6) are taken out.
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103769454A (en) * | 2014-02-13 | 2014-05-07 | 哈尔滨工业大学 | High-temperature forming method of fine-grain TC21 titanium alloy plate |
| CN104451047A (en) * | 2014-11-07 | 2015-03-25 | 西安航空动力股份有限公司 | Hot sizing device and hot sizing method for thin-wall stamping part |
| CN104599664A (en) * | 2014-12-05 | 2015-05-06 | 城林环保技术（上海）有限公司 | Method for integrally manufacturing rectangular wind head of muffler |
| CN105537329A (en) * | 2015-12-24 | 2016-05-04 | 中国工程物理研究院材料研究所 | Preparation method of thin-walled tubular part with revolution curved surface |
| CN106381373A (en) * | 2016-11-25 | 2017-02-08 | 沈阳黎明航空发动机(集团)有限责任公司 | Correction method and device for plate type multilayered structure titanium alloy parts |
| CN106694633A (en) * | 2016-11-28 | 2017-05-24 | 北京动力机械研究所 | High-temperature alloy precise molding cold pressing thermal stability process method |
| CN110773613A (en) * | 2019-12-17 | 2020-02-11 | 凯龙高科技股份有限公司 | Taper pipe flanging forming die |
| CN112371776A (en) * | 2020-10-22 | 2021-02-19 | 中国航发贵州黎阳航空动力有限公司 | Vacuum thermal sizing die and method for engine support case |
| CN113102868A (en) * | 2021-04-20 | 2021-07-13 | 中国直升机设计研究所 | Helicopter main nozzle lobe machining method |
| CN113601116A (en) * | 2021-08-11 | 2021-11-05 | 上海盈达空调设备股份有限公司 | Production process for circular air valve body |
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Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103769454B (en) * | 2014-02-13 | 2016-05-18 | 哈尔滨工业大学 | A kind of hot forming method of thin brilliant TC21 titanium alloy plate |
| CN103769454A (en) * | 2014-02-13 | 2014-05-07 | 哈尔滨工业大学 | High-temperature forming method of fine-grain TC21 titanium alloy plate |
| CN104451047A (en) * | 2014-11-07 | 2015-03-25 | 西安航空动力股份有限公司 | Hot sizing device and hot sizing method for thin-wall stamping part |
| CN104599664B (en) * | 2014-12-05 | 2018-02-09 | 城林环保技术（上海）有限公司 | A kind of matrix silencer public attention method made in one piece |
| CN104599664A (en) * | 2014-12-05 | 2015-05-06 | 城林环保技术（上海）有限公司 | Method for integrally manufacturing rectangular wind head of muffler |
| CN105537329A (en) * | 2015-12-24 | 2016-05-04 | 中国工程物理研究院材料研究所 | Preparation method of thin-walled tubular part with revolution curved surface |
| CN105537329B (en) * | 2015-12-24 | 2017-10-27 | 中国工程物理研究院材料研究所 | A kind of preparation method of surface of revolution thin-wall tube-shaped element |
| CN106381373A (en) * | 2016-11-25 | 2017-02-08 | 沈阳黎明航空发动机(集团)有限责任公司 | Correction method and device for plate type multilayered structure titanium alloy parts |
| CN106694633A (en) * | 2016-11-28 | 2017-05-24 | 北京动力机械研究所 | High-temperature alloy precise molding cold pressing thermal stability process method |
| CN110773613A (en) * | 2019-12-17 | 2020-02-11 | 凯龙高科技股份有限公司 | Taper pipe flanging forming die |
| CN112371776A (en) * | 2020-10-22 | 2021-02-19 | 中国航发贵州黎阳航空动力有限公司 | Vacuum thermal sizing die and method for engine support case |
| CN112371776B (en) * | 2020-10-22 | 2023-03-24 | 中国航发贵州黎阳航空动力有限公司 | Vacuum thermal sizing die and method for engine support case |
| CN113102868A (en) * | 2021-04-20 | 2021-07-13 | 中国直升机设计研究所 | Helicopter main nozzle lobe machining method |
| CN113601116A (en) * | 2021-08-11 | 2021-11-05 | 上海盈达空调设备股份有限公司 | Production process for circular air valve body |
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Application publication date: 20130130 |