CN108941237A - A kind of automotive high intensity steel plate punched moulding process - Google Patents
A kind of automotive high intensity steel plate punched moulding process Download PDFInfo
- Publication number
- CN108941237A CN108941237A CN201810646728.XA CN201810646728A CN108941237A CN 108941237 A CN108941237 A CN 108941237A CN 201810646728 A CN201810646728 A CN 201810646728A CN 108941237 A CN108941237 A CN 108941237A
- Authority
- CN
- China
- Prior art keywords
- steel plate
- high intensity
- moulding process
- plate blank
- automotive high
- 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.)
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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
- B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
- B21C37/02—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of sheets
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
- B21D22/02—Stamping using rigid devices or tools
- B21D22/022—Stamping using rigid devices or tools by heating the blank or stamping associated with heat treatment
-
- 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
- C21D1/68—Temporary coatings or embedding materials applied before or during heat treatment
-
- 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/0081—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for slabs; for billets
-
- 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
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/001—Austenite
Abstract
The present invention provides a kind of automotive high intensity steel plate punched moulding process, include the following steps: that plate raw material 1) is struck out required outer profile steel plate blank；2) above-mentioned blank is heated and is kept the temperature operation, then cooled to 350~380 DEG C, after keeping the temperature 20~30s, coat the ethanol solution of one layer of magnesium silicate in steel plate blank surface, coating thickness is 1~2mm, and applicator surface is dried；3) complete austenitizing will be carried out in step 2) treated steel plate blank is put into heating furnace, is put into hot forming tool rapidly from being taken out in heating furnace, to steel plate blank progress Hot stamping, then 8~12s of pressure maintaining；4) it is cooled to room temperature in a mold with the cooling velocity of 32~35 DEG C/s；5) it takes out molded part and carries out subsequent processing to obtain the final product.The yield rate when high-strength steel sheet manufactures complex shaped components can be improved in technique provided by the invention, while also improving the drawing tensile strength and plasticity of high-strength steel sheet.
Description
Technical field
The invention belongs to automotive high intensity Plate Production technical field, in particular to a kind of automotive high intensity steel plate punched at
Type technique.
Background technique
Auto parts and components are the bases of automobile industry development, are the important components of auto industry.In recent years, automobile heat
The market demand of forming part is in explosive growth trend, and application percentage of the thermoformed part on white body is up to 45%, in advance
Meter the coming five years will double above.Heat stamping and shaping technique is to prepare the more mature method of automobile thermoformed part.
Heat stamping and shaping (Hot stamping/Hotpress forming) technique is also referred to as punching press hardening (Press
It hardening), is the new technology dedicated for automotive high intensity steel plate punched molded part occurred in recent years, and real
One of the key technology technique of existing automotive light weight technology production.Automobile thermoformed structure part is auto parts and components processing enterprise with high-strength
Steel plate (initial strength is 500~600MPa) is raw material, and using stamping parts made from heat stamping and shaping technology, intensity be may be up to
1500MPa, and formed at high temperature almost without rebound, there is formed precision height, molding compared to currently used cold-stamped part
Property good and light-weight equal outstanding advantages.
In thermoforming technology earlier, coating processing is not passed through on the surface of steel plate, and surface can occur during thermoforming
A degree of oxidation generates skin decarburization and oxidation skin effect phenomenon, reduces production efficiency.With the hair of thermoforming technology
Exhibition, coating technology are increasingly being applied to thermoforming steel.Coating can prevent surface oxidation and decarburization in forming process, moreover it is possible to
Corrosion Protection after improving paint dress.The coating drop stamping steel plate developed at present, such as hot pure zinc plating (GI) coating and kirsite
Change (GA) coating etc..But GI and GA coating crackle induction steel matrix cracking easy to form in thermoforming process.
The tensile strength of existing automotive high intensity thermoforming components can reach 1500MPa or more, strong along with steel plate
The increase of degree, compression moulding reduce, and become difficult when manufacturing component with complex shape.With the increasing of armor plate strength
Add the ductility reduction of steel plate, therefore the high position of the degree of finish in component is easy to produce fracture, the rebound of component and wall are stuck up
Qu Bian great, the dimensional accuracy deterioration of component.Therefore, to having superhigh intensity that is high-intensitive, particularly reaching 1500MPa grades or more
Steel plate manufactures component with complex shape and is not easy to, and yield rate is lower, needs to try every possible means to promote its yield rate.
In view of above-mentioned two problems, need to develop a kind of new automotive high intensity steel plate punched moulding process to solve on
State problem.
Summary of the invention
The object of the invention is in order to solve the above-mentioned technical problem, and provide a kind of automotive high intensity steel plate punched molding
Technique, technique provided by the invention can be solved when ultrahigh-strength steel plates manufacture complex shaped components due to being broken and rebound causes
The low problem of yield rate, the tensile strength for the drop stamping steel plate that on the other hand technique of the invention is produced is higher, plasticity compared with
It is good.
To achieve the goals above, a kind of the technical solution adopted by the present invention are as follows: automotive high intensity steel plate punched molding work
Skill includes the following steps:
1) plate raw material is struck out required outer profile steel plate blank using blanking film tool and blanking press；The plate is former
The chemical composition of material are as follows: C:0.23~0.29%, Si:0.22~0.32%, Mn:1.1~1.3%, P:0.007~0.01%,
B:0.002~0.003%, Nb:0.1~0.2%, Cr:1.3~1.6%, remaining is iron and inevitable impurity；
2) steel plate blank obtained by step 1) is subjected to heating and thermal insulation operation, then cooled to 350~380 DEG C, kept the temperature
After 20~30s, the ethanol solution of one layer of magnesium silicate is coated in steel plate blank surface, coating thickness is 1~2mm, by applicator table
It dries in face；
3) complete austenitizing will be carried out in step 2) treated steel plate blank is put into heating furnace, is taken out from heating furnace
It puts into hot forming tool rapidly, Hot stamping is carried out to steel plate blank, then 8~12s of pressure maintaining；
4) it is cooled to room temperature in a mold with the cooling velocity of 32~35 DEG C/s；
5) it takes out molded part and carries out subsequent processing to obtain the final product.
On the one hand punch forming process provided by the invention ensure that the mechanical strength of molded part, tensile strength very well
Up to 1800MPa or more, on the other hand also assures the good plasticity of material, have good material forming accuracy, component
Rebound and wall warpage become smaller, can using one-time formed process can be completed in the past need multiple working procedure that could complete complexity
Shape substantially increases the yield rate when manufacturing complex structural member.Step 2) of the invention-step 4) technique, on the one hand
The plasticity that ensure that material very well while improving steel plate tensile strength, greatly facilitates subsequent hot-forming.Wherein step
3) it must assure that blank is transferred in mold as quickly as possible, it is ensured that steel plate still has good plasticity at the time of molding；And it is high
The cooling operation of certain speed is pressed in pressure maintaining after temperature is stamping again, is on the one hand to control the shape of part, on the other hand
It is that part is made to form uniform martensitic structure, obtains good dimensional accuracy and mechanical performance.
Processing method of the invention enables to steel plate internal fiber flow direction that need not be guaranteed by the impact of secondary loading
Steel plate keeps best intensity and toughness, and is rapidly cooled after part forming, the springback capacity very little after part forming,
Greatly improve material forming accuracy, preferably ensure that parts size precision, for next step automobile body welding lay it is good
Good basis.
Further, in step 2), the operation of the heating and thermal insulation are as follows: the steel plate blank is heated to 760~800
DEG C, keep the temperature 10~12min.
Further, in step 2), the speed of the cooling is 22~26 DEG C/s.
Further, the mass concentration of the magnesium silicate is 2%, is carried out using the magnesium silicate ethanol solution of the mass concentration
Coating, can more preferably guarantee the intensity and plasticity of material.
Further, the temperature of heating furnace described in step 2) is 930~950 DEG C.
Further, the time of the austenitizing is 8~12min.
Further, the subsequent treatment process includes pickling or bead, and carries out trimming and drilling to part
Processing.
Further, the trimming and drilling processing are completed using laser technology.Due to heat-punch member produced by the invention
Intensity is too high, cannot carry out trimming and drilling processing to it with traditional means, it is necessary to complete using laser technology.
Compared with prior art, beneficial effects of the present invention are as follows:
1) the automotive high intensity steel plate of technique of the invention production has higher tensile strength and plasticity, tensile strength
Up to 1800MPa or more, elongation percentage can adapt to improve and become a useful person in the production of complicated shape structural member up to 10% or more
Rate；
2) punch forming process provided by the invention can avoid asking for coating drop stamping steel plate crackle easy to form very well
Topic, cracking breakout are low；
3) technique of the invention can realize the requirement of body lightening production, since armor plate strength produced by the present invention is high,
It thus can reduce its thickness, reduce the weight of vehicle body.
Specific embodiment
In order to make the objectives, technical solutions, and advantages of the present invention clearer, with reference to embodiments to the present invention
It is specifically described, it is necessary to, it is noted that following embodiment is used only for that the present invention is explained and illustrated, be not used to
Limit the present invention.Some nonessential modifications and adaptations that those skilled in the art are made according to foregoing invention content, still belong to
In protection scope of the present invention.
Embodiment 1
A kind of automotive high intensity steel plate punched moulding process, includes the following steps:
1) outer profile steel plate blank needed for plate stamping being gone out using blanking film tool and blanking press；The steel plate blank
Chemical composition are as follows: C:0.23%, Si:0.22%, Mn:1.1%, P:0.007%, B:0.002%, Nb:0.1%, Cr:1.3%,
Remaining is iron and inevitable impurity；
2) steel plate blank obtained by step 1) is subjected to heating and thermal insulation operation, then cooled to 350 DEG C, after keeping the temperature 20s,
The ethanol solution of one layer of magnesium silicate (mass concentration 2%), coating thickness 1mm, by applicator table are coated in steel plate blank surface
It dries in face；
3) complete austenitizing will be carried out in step 2) treated steel plate blank is put into heating furnace, is taken out from heating furnace
It puts into hot forming tool rapidly, Hot stamping is carried out to steel plate blank, then pressure maintaining 8s；
4) it is cooled to room temperature in a mold with the cooling velocity of 32 DEG C/s；
5) it takes out molded part and carries out subsequent processing, including pickling processes, and trimming is carried out to part using laser technology
And drilling processing.
Study on Vehicle Front Wheel House is produced using above-mentioned punch forming process, after tested, tensile strength 1822MPa, surrender
Intensity is 1585MPa, elongation percentage A50It is 10.2%, which forms uniform martensitic structure, obtains good size
Precision produces and processes 200 vehicle front cover structures according to the technique without rebound in production process, and yield rate is up to 96%.With
The crackle for generating 2mm investigates its cracking breakout, and the cracking breakout in finished product is 0.2%.
Embodiment 2
A kind of automotive high intensity steel plate punched moulding process, includes the following steps:
1) outer profile steel plate blank needed for plate stamping being gone out using blanking film tool and blanking press；The steel plate blank
Chemical composition are as follows: C:0.29%, Si:0.32%, Mn:1.3%, P:0.01%, B:0.003%, Nb:0.2%, Cr:1.6%,
Remaining is iron and inevitable impurity；
2) steel plate blank obtained by step 1) is subjected to heating and thermal insulation operation, then cooled to 380 DEG C, after keeping the temperature 30s,
The ethanol solution of one layer of magnesium silicate (mass concentration 2%), coating thickness 2mm, by applicator table are coated in steel plate blank surface
It dries in face；
3) complete austenitizing will be carried out in step 2) treated steel plate blank is put into heating furnace, is taken out from heating furnace
It puts into hot forming tool rapidly, Hot stamping is carried out to steel plate blank, then pressure maintaining 12s；
4) it is cooled to room temperature in a mold with the cooling velocity of 34 DEG C/s；
5) take out molded part and carry out subsequent processing, including pickling or bead, and using laser technology to part into
Row trimming and drilling processing.
Automotive tailgate is produced using above-mentioned punch forming process, after tested, tensile strength 1831MPa, surrender
Intensity is 1601MPa, elongation percentage A50It is 10.6%, which forms uniform martensitic structure, obtains good size
Precision produces and processes 500 automotive tailgate structures according to the technique without rebound in production process, and yield rate is up to 95%.With
The crackle for generating 2mm investigates its cracking breakout, and the cracking breakout in finished product is 0.1%.
Embodiment 3
A kind of automotive high intensity steel plate punched moulding process, includes the following steps:
1) outer profile steel plate blank needed for plate stamping being gone out using blanking film tool and blanking press；The steel plate blank
Chemical composition are as follows: C:0.26%, Si:0.27%, Mn:1.2%, P:0.009%, B:0.0028%, Nb:0.16%, Cr:
1.4%, remaining is iron and inevitable impurity；
2) steel plate blank obtained by step 1) is subjected to heating and thermal insulation operation, then cooled to 365 DEG C, after keeping the temperature 24s,
The ethanol solution of one layer of magnesium silicate (mass concentration 2%), coating thickness 1.3mm, by applicator are coated in steel plate blank surface
It dries on surface；
3) complete austenitizing will be carried out in step 2) treated steel plate blank is put into heating furnace, is taken out from heating furnace
It puts into hot forming tool rapidly, Hot stamping is carried out to steel plate blank, then pressure maintaining 10s；
4) it is cooled to room temperature in a mold with the cooling velocity of 35 DEG C/s；
5) it takes out molded part and carries out subsequent processing, including bead, and trimming is carried out to part using laser technology
And drilling processing.
Using ceiling outside plate on above-mentioned punch forming process production automobile, after tested, tensile strength 1892MPa is bent
Taking intensity is 1621MPa, elongation percentage A50It is 12.3%, which forms uniform martensitic structure, obtains good ruler
Very little precision produces and processes ceiling outer panel structure on 1000 automobiles according to the technique, yield rate reaches without rebound in production process
97%.Its cracking breakout is investigated to generate the crackle of 1mm, the cracking breakout in finished product is 0.06%.
Claims (8)
1. a kind of automotive high intensity steel plate punched moulding process, which comprises the steps of:
1) plate raw material is struck out required outer profile steel plate blank using blanking film tool and blanking press；The plate raw material
Chemical composition are as follows: C:0.23~0.29%, Si:0.22~0.32%, Mn:1.1~1.3%, P:0.007~0.01%, B:
0.002~0.003%, Nb:0.1~0.2%, Cr:1.3~1.6%, remaining is iron and inevitable impurity；
2) steel plate blank obtained by step 1) is subjected to heating and thermal insulation operation, then cooled to 350~380 DEG C, heat preservation 20~
After 30s, the ethanol solution of one layer of magnesium silicate is coated in steel plate blank surface, coating thickness is 1~2mm, and applicator surface is dried in the air
It is dry；
3) complete austenitizing will be carried out in step 2) treated steel plate blank is put into heating furnace, is taken out from heating furnace rapid
It puts into hot forming tool, Hot stamping is carried out to steel plate blank, then 8~12s of pressure maintaining；
4) it is cooled to room temperature in a mold with the cooling velocity of 32~35 DEG C/s；
5) it takes out molded part and carries out subsequent processing to obtain the final product.
2. automotive high intensity steel plate punched moulding process according to claim 1, which is characterized in that described in step 2)
The operation of heating and thermal insulation are as follows: the steel plate blank is heated to 760~800 DEG C, keeps the temperature 10~12min.
3. automotive high intensity steel plate punched moulding process according to claim 1, which is characterized in that described in step 2)
Cooling speed is 22~26 DEG C/s.
4. automotive high intensity steel plate punched moulding process according to claim 1, which is characterized in that the matter of the magnesium silicate
Measuring concentration is 2%.
5. automotive high intensity steel plate punched moulding process according to claim 1, which is characterized in that add described in step 3)
The temperature of hot stove is 930~950 DEG C.
6. automotive high intensity steel plate punched moulding process according to claim 1, which is characterized in that the austenitizing
Time is 8~12min.
7. automotive high intensity steel plate punched moulding process according to claim 1, which is characterized in that the subsequent processing work
Skill includes pickling or bead, and carries out trimming and drilling processing to part.
8. automotive high intensity steel plate punched moulding process according to claim 7, which is characterized in that the trimming and drilling
Processing is completed using laser technology.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810646728.XA CN108941237A (en) | 2018-06-21 | 2018-06-21 | A kind of automotive high intensity steel plate punched moulding process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810646728.XA CN108941237A (en) | 2018-06-21 | 2018-06-21 | A kind of automotive high intensity steel plate punched moulding process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108941237A true CN108941237A (en) | 2018-12-07 |
Family
ID=64491084
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| CN201810646728.XA Pending CN108941237A (en) | 2018-06-21 | 2018-06-21 | A kind of automotive high intensity steel plate punched moulding process |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111112418A (en) * | 2019-12-04 | 2020-05-08 | 苏州格鼎精密电子有限公司 | Metal sheet metal part stamping process |
| CN112893507A (en) * | 2021-01-15 | 2021-06-04 | 滁州美杰精密部件制造有限公司 | Forming method for side plate machining |
| CN113182374A (en) * | 2021-04-30 | 2021-07-30 | 合肥合锻智能制造股份有限公司 | Thermal forming method of high-strength structural member |
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| CN101623823A (en) * | 2009-06-22 | 2010-01-13 | 胡平 | Automatic production line for warm/hot forming complete equipment of energy-saving high-strength sheet steel |
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| CN111112418A (en) * | 2019-12-04 | 2020-05-08 | 苏州格鼎精密电子有限公司 | Metal sheet metal part stamping process |
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| CN113182374A (en) * | 2021-04-30 | 2021-07-30 | 合肥合锻智能制造股份有限公司 | Thermal forming method of high-strength structural member |
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Application publication date: 20181207 |