CN104532129A - Galvanization-free high-strength and plasticity cold-rolled stainless steel plate for automobile and manufacturing method of galvanization-free high-strength and plasticity cold-rolled stainless steel plate - Google Patents
Galvanization-free high-strength and plasticity cold-rolled stainless steel plate for automobile and manufacturing method of galvanization-free high-strength and plasticity cold-rolled stainless steel plate Download PDFInfo
- Publication number
- CN104532129A CN104532129A CN201510005588.4A CN201510005588A CN104532129A CN 104532129 A CN104532129 A CN 104532129A CN 201510005588 A CN201510005588 A CN 201510005588A CN 104532129 A CN104532129 A CN 104532129A
- Authority
- CN
- China
- Prior art keywords
- temperature
- stainless steel
- cold
- austenite
- strength
- 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.)
- Granted
Links
- 229910001220 stainless steel Inorganic materials 0.000 title claims abstract description 55
- 239000010935 stainless steel Substances 0.000 title claims abstract description 55
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 19
- 229910001566 austenite Inorganic materials 0.000 claims abstract description 127
- 229910000734 martensite Inorganic materials 0.000 claims abstract description 86
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 56
- 238000000034 method Methods 0.000 claims abstract description 53
- 238000005097 cold rolling Methods 0.000 claims abstract description 24
- 238000005266 casting Methods 0.000 claims abstract description 22
- 238000005192 partition Methods 0.000 claims abstract description 21
- 238000005096 rolling process Methods 0.000 claims abstract description 13
- 229910000831 Steel Inorganic materials 0.000 claims description 87
- 239000010959 steel Substances 0.000 claims description 87
- 238000005098 hot rolling Methods 0.000 claims description 37
- 238000001816 cooling Methods 0.000 claims description 34
- 230000009466 transformation Effects 0.000 claims description 33
- 238000000137 annealing Methods 0.000 claims description 20
- 230000009467 reduction Effects 0.000 claims description 20
- 239000000203 mixture Substances 0.000 claims description 15
- 229910052799 carbon Inorganic materials 0.000 claims description 12
- 229910052719 titanium Inorganic materials 0.000 claims description 11
- 239000010960 cold rolled steel Substances 0.000 claims description 10
- 229910052758 niobium Inorganic materials 0.000 claims description 10
- 229910052720 vanadium Inorganic materials 0.000 claims description 10
- 238000009413 insulation Methods 0.000 claims description 9
- 241001062472 Stokellia anisodon Species 0.000 claims description 7
- 229910052748 manganese Inorganic materials 0.000 claims description 5
- 238000005554 pickling Methods 0.000 claims description 5
- 238000010792 warming Methods 0.000 claims description 5
- 229910052717 sulfur Inorganic materials 0.000 claims description 4
- 238000007669 thermal treatment Methods 0.000 claims description 4
- 229910052750 molybdenum Inorganic materials 0.000 claims description 3
- 229910052759 nickel Inorganic materials 0.000 claims description 3
- 229910052698 phosphorus Inorganic materials 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 229910052757 nitrogen Inorganic materials 0.000 claims description 2
- 230000008569 process Effects 0.000 abstract description 38
- 238000010438 heat treatment Methods 0.000 abstract description 20
- 239000000463 material Substances 0.000 abstract description 13
- 238000005728 strengthening Methods 0.000 abstract description 10
- 238000005516 engineering process Methods 0.000 abstract description 9
- 229910000963 austenitic stainless steel Inorganic materials 0.000 abstract description 6
- 230000000717 retained effect Effects 0.000 abstract description 2
- 238000005272 metallurgy Methods 0.000 abstract 1
- 239000012071 phase Substances 0.000 description 49
- 238000002791 soaking Methods 0.000 description 26
- 238000005260 corrosion Methods 0.000 description 21
- 230000007797 corrosion Effects 0.000 description 19
- 230000000694 effects Effects 0.000 description 17
- 239000006104 solid solution Substances 0.000 description 17
- 230000002829 reductive effect Effects 0.000 description 16
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 13
- 229910052725 zinc Inorganic materials 0.000 description 13
- 239000011701 zinc Substances 0.000 description 13
- 125000004432 carbon atom Chemical group C* 0.000 description 11
- 230000036961 partial effect Effects 0.000 description 11
- 238000001556 precipitation Methods 0.000 description 11
- 229910001567 cementite Inorganic materials 0.000 description 9
- KSOKAHYVTMZFBJ-UHFFFAOYSA-N iron;methane Chemical compound C.[Fe].[Fe].[Fe] KSOKAHYVTMZFBJ-UHFFFAOYSA-N 0.000 description 9
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 8
- 230000015572 biosynthetic process Effects 0.000 description 8
- 238000013461 design Methods 0.000 description 8
- 238000005482 strain hardening Methods 0.000 description 8
- 239000000126 substance Substances 0.000 description 7
- 239000000243 solution Substances 0.000 description 6
- 238000003723 Smelting Methods 0.000 description 5
- 230000009286 beneficial effect Effects 0.000 description 5
- 229910052804 chromium Inorganic materials 0.000 description 5
- 239000011248 coating agent Substances 0.000 description 5
- 238000000576 coating method Methods 0.000 description 5
- 238000009792 diffusion process Methods 0.000 description 5
- 229910052742 iron Inorganic materials 0.000 description 5
- 238000002360 preparation method Methods 0.000 description 5
- 238000012545 processing Methods 0.000 description 5
- 238000005496 tempering Methods 0.000 description 5
- 230000003245 working effect Effects 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 229910000794 TRIP steel Inorganic materials 0.000 description 4
- 230000008901 benefit Effects 0.000 description 4
- 230000008859 change Effects 0.000 description 4
- 239000013078 crystal Substances 0.000 description 4
- 238000005246 galvanizing Methods 0.000 description 4
- 239000011159 matrix material Substances 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- 239000004576 sand Substances 0.000 description 4
- 238000009628 steelmaking Methods 0.000 description 4
- 229910001563 bainite Inorganic materials 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 229910001039 duplex stainless steel Inorganic materials 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 238000010791 quenching Methods 0.000 description 3
- 230000000171 quenching effect Effects 0.000 description 3
- 230000007704 transition Effects 0.000 description 3
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 2
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 230000004069 differentiation Effects 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 150000004767 nitrides Chemical class 0.000 description 2
- 238000002161 passivation Methods 0.000 description 2
- 238000011069 regeneration method Methods 0.000 description 2
- 230000006641 stabilisation Effects 0.000 description 2
- 238000011105 stabilization Methods 0.000 description 2
- 239000003351 stiffener Substances 0.000 description 2
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 229910000885 Dual-phase steel Inorganic materials 0.000 description 1
- 235000010724 Wisteria floribunda Nutrition 0.000 description 1
- -1 and thereafter Substances 0.000 description 1
- 230000003190 augmentative effect Effects 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 229910052729 chemical element Inorganic materials 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 239000003500 flue dust Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 230000001172 regenerating effect Effects 0.000 description 1
- 230000008261 resistance mechanism Effects 0.000 description 1
- 230000000452 restraining effect Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000004626 scanning electron microscopy Methods 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000002910 structure generation Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
- 238000010301 surface-oxidation reaction Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 238000009864 tensile test Methods 0.000 description 1
- 239000011787 zinc oxide Substances 0.000 description 1
Landscapes
- Heat Treatment Of Sheet Steel (AREA)
Abstract
The invention relates to a galvanization-free high-strength and plasticity cold-rolled stainless steel plate for an automobile and a manufacturing method of the galvanization-free high-strength and plasticity cold-rolled stainless steel plate, and belongs to the technical field of metallurgy. The galvanization-free high-strength and plasticity cold-rolled stainless steel plate comprises, by weight, 11.0-17.0% of Cr, 0.01-0.12% of C, 0.2-0.5% of Mn, 0.2-1.1% of Si, 0.005-0.5% of Al, less than 0.3% of Ni, less than 0.2% of Nb, less than 0.2% of Ti, less than 0.2% of V, less than 0.1% of Mo, less than 0.03% of Cu, less than 0.05% of N, less than 0.003% of S and the balance Fe. The manufacturing method of the galvanization-free high-strength and plasticity cold-rolled stainless steel plate comprises the steps of casting, heat rolling, cold rolling and heat treatment based on the quenching-partition (Q&P) technology. According to the galvanization-free high-strength and plasticity cold-rolled stainless steel plate, the process of surface galvanization is omitted, the material cost is obviously lower than that of austenitic stainless steel, texture comprises martensite, retained austenite and selectable ferrite, good strength and plasticity are combined, and the galvanization-free high-strength and plasticity cold-rolled stainless steel plate is especially suitable for structural parts, strengthening parts and the like for manufacturing automobiles.
Description
Technical field
The invention belongs to metallurgical technology field, particularly a kind of automobile is with exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet and manufacture method thereof.
Background technology
Along with developing rapidly of automotive industry, China has become third place in the world large automobile production state and second largest automobile consumption state, produces automobile year more than 2,000 ten thousand, consumes all kinds of automobile sheet material year more than 2,200 ten thousand tons.Current, reduction oil consumption and the security of raising vehicle body are the outstanding requests in development of automobile.Alleviating tare is the effective way reducing oil consumption, but, if only reduce the sectional dimension of automobile component, bus body strength can be caused again not enough, therefore, in order to meet the requirement reducing weight and improve vehicle body security simultaneously, automobile steel must need to improve intensity.At present, intensity and plasticity and toughness all preferably AHSS (AHSS) become the material of automobile manufacturing field focus development and application, and it comprises two-phase (DP) steel, phase-change induced plastic (TRIP) steel and quenching-partition (Q & P) steel etc.In general-utility car and superior automobile, the usage ratio of AHSS reaches 50% and 80% respectively.
Long lifetime is another important development requirement of automobile steel.It can strengthen vehicle safety, reduces automobile Life cycle cost, improves the level of resources utilization.The standard in work-ing life of automobile steel was increased to current ~ 12 year by previous 6 years, also can be increased to synchronous with the integeral vehicle life of ~ 20 years soon.Solidity to corrosion is the key factor determining automobile steel work-ing life.But the solidity to corrosion belonging to the AHSS of straight carbon steel can not meet the requirement in automobile steel work-ing life at all, the Improving Measurements extensively adopted at present is at its surface galvanizing.The usage ratio of AHSS in general-utility car and superior automobile of surface galvanizing has accounted for 60% and 90% of whole AHSS, and emphasis is applied to the chassis of corrosion-vulnerable, forward engine room, luggage, the position such as car door and outer covering piece.
Pot galvanize DP steel is the automobile AHSS that current application percentage is maximum.Such as patent CN101781739 discloses the cold rolling DP steel of a kind of pot galvanize: its preparation technology is mainly and cold-reduced sheet is heated to (austenite+ferrite) two-phase region temperature 720 ~ 820 DEG C insulation 25 ~ 100s, ~ zinc the pond of 460 DEG C is cooled to again with the speed of 15 ~ 35 DEG C/s, carry out the pot galvanize of 10 ~ 30s, then, be cooled to room temperature with the speed of > 15 DEG C/s, in whole process of cooling, austenite main phase becomes martensite; Finished product tissue is mainly martensite and ferrite; Finished product obtains the tensile strength of 610 ~ 670MPa and the tension set of 20 ~ 26%.Pot galvanize DP steel has fully utilized the advantage that martensite intensity is high and ferrite plasticity is good, but because the intensity of iron-clad horses two-phase and plasticity differ greatly, its formability such as hole expandability and bending is on the low side.
Pot galvanize TRIP steel is a kind of novel automobile AHSS.Such as patent CN1985016 discloses a kind of pot galvanize Cold-Rolled TRIP Steel: its preparation technology is mainly and cold-reduced sheet is heated to (austenite+ferrite) two-phase region of 750 ~ 900 DEG C and is incubated 10s ~ 360s, then is cooled to the bainitic transformation temperature range (B of 350 ~ 500 DEG C with the speed of 2 ~ 200 DEG C/s
s~ B
f) and be incubated < 600s, make austenite fraction generation bainitic transformation, then, immerse the zinc pond of 450 ~ 600 DEG C and be incubated 5 ~ 120s, make carbon by bainite to not changing enrichment in austenite carrying out pot galvanize simultaneously, finally, be cooled to < 250 DEG C with the speed of > 5 DEG C/s, partial austenitic remains to room temperature; Finished product tissue is mainly bainite, ferrite and residual austenite; Finished product obtains the tensile strength of 590 ~ 1080MPa and the tension set of 18 ~ 36%.Pot galvanize TRIP steel make use of residual austenite in finished product processing, there is martensitic transformation in deformation process, alleviates the stress concentration in material and improves formability and the plasticity and toughness of material.But although austenite can produce drawing hardening effect, its content is limited, and content accounts for the bainite of major portion and ferrite intensity is lower, therefore, under equalization component system, and the low cross-intensity of pot galvanize TRIP steel.
Pot galvanize Q & P steel is a kind of up-to-date automobile AHSS, such as patent W02014075405 discloses a kind of pot galvanize cold rolling Q & P steel: after its preparation technology is mainly and cold-reduced sheet is heated to 840 ~ 920 DEG C of insulation 40 ~ 80s, be cooled to (austenite+ferrite) two-phase region of 720 ~ 800 DEG C with the speed of 3 ~ 10 DEG C/s, then be cooled to the martensitic transformation temperature interval (M of 260 ~ 360 DEG C with the speed of>=50 DEG C/s
s~ M
f), make austenite fraction generation martensitic transformation, then, immersing the zinc pond of 460 ~ 470 DEG C and be incubated 60 ~ 120s, making carbon by martensite to not changing enrichment in austenite carrying out pot galvanize, finally simultaneously, be cooled to room temperature, partial austenitic remains to room temperature; Finished product is organized as martensite, ferrite and residual austenite; Finished product obtains the tensile strength of 980 ~ 1200MPa and the tension set of 15 ~ 22%.Pot galvanize Q & P steel has fully utilized the advantage of first two steel, obtains the combination of good intensity, plasticity and toughness and plasticity.
But there is the problem of three aspects in the use of galvanized sheet.One, automobile galvanized sheet is in secondary processing and automobile day-to-day operation, accidental thrusts, once surperficial zinc layers is damaged, its solidity to corrosion, by degradation, directly threatens its work-ing life and car load safety.Its two, China scraps 400 ~ 6,000,000 automobiles every year, but automobile galvanized sheet is reclaiming in smelting process again, and quite a few zinc is mixed in flue dust with the form of zinc oxide and enters air.This causes the zinc recovery of China's galvanized sheet very low, even if in iron and steel industry developed country, the zinc recovery of galvanized sheet is also lower than 80%.And the zinc resource situation of China is very severe again, the reserves of zinc resource and the static state on reserves basis ensure that the time limit is only 12 and 18 years respectively.This seriously governs the long term growth of China's automobile industry.Its three, when galvanized sheet is smelted again, the zinc do not volatilized can be mixed in molten steel, and thereafter, zinc is difficult to be separated from molten steel, and this can inevitably cause zinc constantly to deposit in new smelting steel.This brings great difficulty to the Composition Control in steel recycle process of overall importance.
But there is not the problem of this three aspect in stainless steel.One, stainless steel contains the anti-corrosion element Cr of > 11%, and surface can form the fine and close passive film containing Cr, therefore has good solidity to corrosion, does not need surface galvanizing; And its surface passivated membrane has self-passivation function, can self-regeneration affected area.Therefore, stainless steel has good and stable solidity to corrosion.Its two, stainless steel is reclaiming in smelting process again, can be easy to realize close to 100% recovery rate, this greatly reduces the degree of dependence of stainless steel to Mineral resources in recycle and long term growth process.Its three, stainless steel scrap and new composition of steel are unified, smelting technology is simple again, this greatly reduces the Composition Control difficulty in steel recycle process of overall importance.
At present, high-strength vehicle stainless steel mainly contains two types: one is metastable state austenitic stainless steel; One is (martensite+ferrite) duplex stainless steel.They are mainly used in vehicle body, the structural part and stiffener etc. of the public transportation instruments such as train, subway and passenger vehicle.
Patent CN101984123 discloses a kind of speed train cars metastable state austenitic stainless steel: its preparation technology is mainly hot-rolled sheet at 1050 ~ 1100 DEG C of solution treatment 10 ~ 30min, tissue all becomes austenite mutually, then, hot-rolled sheet pickling, then carry out total reduction be 70 ~ 88% cold rolling, partial austenitic becomes martensite mutually, finally, cold-reduced sheet 780 ~ 1100 DEG C annealing 1 ~ 3min, martensite generation tempering, part tempered martensite know from experience reverse transformation be austenite; Finished product is organized as austenite and tempered martensite; Finished product obtains the tensile strength of 850 ~ 1090MPa and the tension set of 28 ~ 48%.Metastable state austenitic stainless steel make use of austenite phase transformation and twinning induced plasticity, work hardening rate is high and martensite intensity is high feature, obtains good intensity and plasticity; But owing to containing the expensive Ni of 7 ~ 8%, its material cost is too high.
Patent CN1550565 discloses a kind of structural member (martensite+ferrite) duplex stainless steel: its preparation technology is mainly and cold-reduced sheet is heated to (austenite+ferrite) the two-phase region temperature of 850 ~ 1250 DEG C and is incubated 30s, then, be cooled to room temperature with the speed of > 1 DEG C/s, in process of cooling, austenite main phase becomes martensite; Finished product is organized as martensite and ferrite; Finished product obtains the tensile strength of 730 ~ 1200MPa and the tension set of 10 ~ 15%.(martensite+ferrite) duplex stainless steel does not contain Ni substantially, the cost of material is low, fully utilize the advantage that martensite intensity is high and ferrite plasticity is good, but because the intensity of iron-clad horses two-phase and plasticity differ greatly, its formability such as hole expandability and bending is on the low side.
Summary of the invention
The object of this invention is to provide a kind of automobile with exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet and manufacture method thereof, by reasonable component design and processes step, for preparing excellent property requires all higher automobile structural part and stiffener for the manufacture of to intensity, plasticity and solidity to corrosion.
Automobile of the present invention is with exempting from the composition of zinc-plated high strength and plasticity cold rolled stainless steel sheet by weight percentage containing Cr11.0 ~ 17.0%, C 0.01 ~ 0.12%, Mn 0.2 ~ 0.5%, Si 0.2 ~ 1.1%, Al 0.005 ~ 0.5%, Ni < 0.3%, Nb < 0.2%, Ti < 0.2%, V < 0.2%, Mo < 0.1%, Cu < 0.03%, N < 0.05%, P < 0.03%, S < 0.003%, surplus is Fe.
Automobile of the present invention is 280 ~ 870MPa by the yield strength exempting from zinc-plated high strength and plasticity cold-rolling stainless steel, and tensile strength is 500 ~ 1280MPa, and tension set is 15.5 ~ 29.0%, strength and ductility product 12000 ~ 27500MPa%.
Automobile of the present invention is with exempting from the tissue of zinc-plated high strength and plasticity cold rolled stainless steel sheet, and the volume fraction of residual austenite is 1 ~ 15%, and ferritic volume fraction is 0 ~ 65%, and all the other are martensite.
The automobile of the present invention manufacture method exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet is carried out according to the following steps:
1, cast: smelt by set component, and ingot casting or continuously cast bloom are made in casting;
2, hot rolling: ingot casting or continuously cast bloom are heated to 1100 ~ 1250 DEG C, insulation 0.5 ~ 3h, then carries out hot rolling, start rolling temperature is 1050 ~ 1200 DEG C, and finishing temperature is 750 ~ 900 DEG C, and hot rolling total reduction is 92 ~ 98%, finally batch at 450 ~ 650 DEG C, obtain hot-rolled steel sheet;
3, cold rolling: to be annealed by hot-rolled steel sheet, annealing temperature is 750 ~ 950 DEG C, and the time is 4min ~ 480min, is then cooled to normal temperature, pickling removing hot-rolled sheet scale on surface, then carries out cold rolling, and cold rolling total reduction is 40 ~ 90%, obtains cold-rolled steel sheet;
4, thermal treatment:
4.1, cold-rolled steel sheet is heated to temperature T
a, insulation 0.5 ~ 10min carries out austenitizing; Wherein A
c1< T
a< A
c5, described A
c1for the temperature that tissue is austenite+ferrite two-phase by single alpha ferrite phase in version, described A
c5for organizing the temperature being changed into single delta ferrite phase by austenite+ferrite two-phase;
4.2, then cold-rolled steel sheet is cooled to temperature T with the rate of cooling of 15 ~ 100 DEG C/s
q, make austenite fraction become martensite mutually; Wherein M
s< T
q< M
f, described M
sfor tissue by austenite to temperature martensitic transformation, described M
ffor tissue is by the end temp of austenite to martensitic transformation;
4.3, again cold-rolled steel sheet is warming up to temperature T
p, insulation 0.5 ~ 60min carries out C partition; Wherein T
q≤ T
p< 600 DEG C;
4.4, finally cold-rolled steel sheet being cooled to room temperature with the rate of cooling of 10 ~ 100 DEG C/s, obtaining automobile with exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet.
The present invention's microstructure evolution is in the fabrication process as follows:
The Heating temperature of 1150 ~ 1250 DEG C before hot rolling, for the above-mentioned stainless steel substantially not containing Ni, normally its (austenite+ferrite) two-phase region or single delta ferrite phase region, this is because contain the Cr higher than 11% in above-mentioned stainless steel, its high temperature austenite phase region is heavily compressed, to such an extent as to most of C content lower than 0.05% stainless steel high temperature there is not single austenite phase field;
In course of hot rolling, austenite and ferrite are while rolling deformation, also can soften with the form of recrystallize and reply, this makes their work hardening capacity not high all the time in whole course of hot rolling, in addition, austenite is also along with the reduction of temperature constantly becomes ferrite mutually with the carrying out of distortion; At the end of hot rolling, most of austenite becomes ferrite mutually, and ferrite substantially shows as through-thickness and flattens, elongates but the not high deformed state of inner work hardening capacity along rolling direction; When hot rolling end temp is lower or above-mentioned stainless A
c1when temperature is higher, hot rolling microstructure is all deformation ferritic structure;
In process of cooling after hot rolling, if still containing austenite in hot rolling microstructure, then it can undergo phase transition; This phase transformation is ferrite transformation when rate of cooling is slower, is martensitic transformation when rate of cooling is very fast; To be the Cr owing to adding > 11% in above-mentioned stainless steel, Cr be improves the element of hardenability of steel for this, and therefore, above-mentioned stainless hardening capacity is fine, austenite one only there is martensite or ferrite transformation, there is not bainitic transformation;
In hot rolling and roller repairing process, along with the reduction of temperature and the accumulation of distortion, have (Cr, Fe) in ferrite matrix
23c
6separate out; And for the stainless steel containing microalloy elements such as Nb, Ti, V, in ferrite, also have the carbide MC of these microalloy elements to separate out;
The annealing of hot-rolled sheet is carried out in single ferritic recrystallization temperature interval usually, this is to make hot rolling microstructure be single recrystallize ferritic structure with the form evolution of recrystallize, thus in follow-up cold-rolled process, obtain lower rolling load and comparatively uniform cold rolling microstructure;
In cold-rolled process, only constantly can there is work hardening in the single ferritic structure in cold-reduced sheet, and occur without softening, and at the end of cold rolling, cold rolling microstructure is the single deformation ferritic structure that work hardening capacity is higher;
Cold-reduced sheet is heated to austenitizing temperature T
a, deformation ferritic structure generation austenitizing; For most of C content higher than 0.05% stainless steel, there is single austenite phase field in its high temperature, the austenitizing of this processing step comprises partial austenitizing and whole austenitizing two kinds may; And for most of C content lower than 0.05% stainless steel, there is not single austenite phase field in its high temperature, and only has (austenite+ferrite) two-phase region, and the austenitizing of this processing step can only be partial austenitizing; When austenitizing is partial austenitizing, temperature T
adetermine the high temperature austenite of formation and ferritic Phase Proportion; Can not be there is modal change in high temperature iron ferritic, be retained in the finished product tissue of room temperature in follow-up heat treatment process always; For the stainless steel containing microalloy elements such as Nb, Ti, V, also with the partly or entirely dissolving of the carbide of these microalloy elements in austenitization;
Be quenched to temperature T
q, T
qmartensite start temperature M can be chosen at
swith martensitic transformation end temp M
fbetween, such austenite can partial phase change be martensite, the non-phase transformation of part, T
qvalue determines the Phase Proportion of martensite and non-transformed austenite;
Be incubated or be warming up to temperature T
psuch one side can stop proceeding of martensitic transformation, make the martensite generation tempering be phase-changed on the other hand, its inner oversaturated solid solution C atom can spread in the strong austenite of molten C ability, thus make austenite more stable due to the raising of C concentration, also more easily remain to room temperature; Temperature T
phigher, the rate of diffusion of solid solution C atom is faster; Martensite is in the process of tempering, if in steel, Si and Al content is lower (one (Si+A1) < 1.0%), then one also has cementite (Fe, Cr)
3c separates out; If in steel, Si and Al content is higher (one (Si+Al) > 1.0%), then one does not have the precipitation of cementite; When there being cementite to separate out in tempered martensite, in it, the concentration of solid solution C atom can reduce, then solid solution C atom can be weakened to the diffusion in austenite, even can be reversed;
For the stainless steel containing microalloy elements such as Nb, Ti, V, in quenching and partition process, also with the precipitation of the carbide MC of these microalloy elements.The formation of these carbide is the same with the formation of cementite, can reduce solid solution C atom to the diffusion in austenite; But these carbide size are comparatively tiny, precipitation strength effect to a certain extent can be played;
By partition temperature T
pbe quenched to room temperature, therebetween, partial austenitic can remain to room temperature, and partial austenitic can become martensite mutually.
In the chemical composition of steel of the present invention, the effect of each chemical element and the principle of design of content thereof are:
Cr: be most important anti-corrosion element in stainless steel, its corrosion resistance mechanism is the fine and close passive film forming rich Cr at stainless steel surface, hinder external agency and matrix to react, and this passive film has self-passivation function, can self-regeneration affected area.In reality, stainless Cr content depends on the corrosion proof requirement of material to a great extent, and for making stainless steel of the present invention have good and stable solidity to corrosion, thus reach and exempt from zinc-plated object, its Cr content should more than 11%.And Cr also improves the hardening capacity of steel, the interpolation of a large amount of Cr makes stainless steel have fabulous hardening capacity, promotes that the Critical cooling speed of austenite generation martensitic transformation is very low, is extremely beneficial to the finished product tissue that steel of the present invention obtains design;
But, Cr promotes ferrite former, the formation of high temperature austenite can be suppressed, in order to obtain designed finished product tissue, the restraining effect of Cr to austenitic formation needs to increase austenite former C, Mn, Ni and balances, and the increase of C, Mn excessively can promote the strength level of material, this just needs Optimization Balancing between Cr and C, Mn.And, both raised the cost higher than the Cr content of 17%, toughness, plasticity and weld processibility can be reduced again.Therefore, designing Cr content is 11 ~ 17%;
C: be most important strengthening element in steel, multiple strengthening effect can be played.In steel of the present invention, due to adding in a large number of Cr, make the formation of high temperature austenite be subject to very large suppression, now, C promotes that the effect that high temperature austenite is formed is particularly important; C can also improve the hardening capacity of steel, promotes that high temperature austenite becomes the martensite of high dislocation density mutually under faster process for cooling less demanding to rate of cooling, plays the effect of phase transformation strengthening.Major part C can be solid-solution in martensite, plays solution strengthening effect.C can also with the combinations such as carbide Nb, Ti, V, Mo in steel, form tiny hard precipitated phase, play precipitation strength effect; In partition technological process, the C be solid-solution in martensite by diffusing in austenite, improve stabilization of austenite, promoting that it remains to room temperature.Therefore, design C content, higher than 0.01%, is the intensity that will be improved steel by multiple augmented form, ensures to obtain a certain amount of residual austenite, to improve plasticity on high strength basis simultaneously;
But when C content is too high, the too much martensitic fragility of solid solution C can be excessively strong, thus the plasticity of infringement steel and toughness.And C content is too high also can cause Carbide Precipitation too much, and the solidity to corrosion of steel and weldability can be caused excessively poor.Therefore, designing C content is 0.01 ~ 0.12%;
Mn: the effect in steel and C have similarity largely.Mn can solution strengthening; Austenitic stability can be improved, promote the formation of high temperature austenite, promote that high temperature austenite remains to room temperature; The hardening capacity of steel can also be improved, reduce the Critical cooling speed of austenite generation martensitic transformation.With C unlike, Mn except forming MnS, not easily form other precipitated phase, not easily damage plasticity and the toughness of steel;
But along with the rising of Mn content, the austenite ratio under high temperature raises, ratio of ferrite reduces, and obtains ferritic difficulty and increases, be difficult to ensure that finished product is organized as the heterogeneous structure of design after thermal treatment.And steel plate resistance to deformation in cold working process increases, and difficulty of processing increases, and in addition, steel plate solidity to corrosion also can reduce; Therefore, designing Mn content is 0.2 ~ 0.5%;
Si: can solution strengthening effect be played.In partition technological process, Si suppresses cementite in tempered martensite to be separated out, and makes more C diffuse in austenite, is beneficial to austenite and remains to room temperature; But, Si too high levels, hot procedure light plate surface easily forms the oxide compound being difficult to remove, the surface quality of infringement steel plate and coating performance; For the steel plate needing Coating, Si content is restricted; But coating exempted from by steel of the present invention, less containing quantitative limitation to Si, therefore, design Si content is 0.2 ~ 1.1%;
Al: the effect in steel and Si are comparatively similar, Al can solution strengthening, Al can suppress the precipitation of cementite, and, Al is used as reductor during steel-making usually, the detrimental effect of Al to plate surface quality and coating performance is weaker than Si, with Al Substitute For Partial Si, can alleviate the infringement to plate surface quality and coating performance; But during Al too high levels, can increase the viscosity of slag during steel-making, reduce heat conduction and the flowing property of molten steel, the casting properties of infringement molten steel, therefore, design Al content is 0.005 ~ 0.5%;
Ni: the stability that can improve stainless steel surface passive film, especially in strong corrosive media, Ni promotes that high temperature austenite is formed, and also promotes that austenite remains to room temperature; Ni is the important composition element of austenitic stainless steel; But the price of Ni will be significantly higher than Cr, significantly improves material cost, belongs to control element in stainless steel of the present invention, the Ni because steel scrap brings should be reduced as far as possible; Therefore, designing Ni content is < 0.3%;
Ti, Nb, V: be strong carbon, nitride forming element, Ti or strong sulfide forming element, they are stabilizing elements conventional in stainless steel, prevent from being formed the carbide of rich Cr and cause matrix Cr concentration to reduce, then causing material solidity to corrosion to reduce.They are combined with C, can form tiny carbide, can play precipitation strength effect; The precipitation of their carbide betides in hot rolling and roller repairing process usually, can refinement hot rolling microstructure, this refining effect can heredity in follow-up microstructure evolution, finally play refined crystalline strengthening effect; But the precipitation of their carbide can reduce overall solid solution C content in steel, in partition process, can reduce solid solution C to the diffusion in austenite, austenite is hindered to remain to room temperature.Therefore, the equal < 0.2% of Ti, Nb, V three's content is designed;
N: the effect in steel and C quite similar.C has multiple strengthening effect.But the interpolation on the one hand due to N in smelting process is more difficult than C a lot; On the other hand, because N can form nitride in the liquid phase with Al, Ti etc., then become the formation core of oxide compound, sulfide, they easily develop into thicker inclusion, the toughness of infringement steel; Therefore, designing N content is < 0.05%;
Mo: stainless solidity to corrosion can be improved, the especially corrosive nature of anti-chlorine ion and reductant and the solidity to corrosion of weld.But add Mo and can increase material cost, under guarantee solidity to corrosion prerequisite, one does not add Mo; Therefore, designing Mo content is < 0.1%.；
Cu: stainless solidity to corrosion can be improved, the stainless steel steel scrap added when mainly coming from steel-making.But meeting under use properties requirement, one does not add Cu.Therefore, designing Cu content is < 0.03%;
P, S: the impurity element in the raw material added when being steel-making, can have a strong impact on stainless solidity to corrosion and processibility, should reduce as far as possible; Therefore, design P content is < 0.03%, S content is < 0.003%.
The automobile of the present invention manufacture method exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet comprises casting, hot rolling, annealing, pickling, cold rolling and thermal treatment; Flow process principle is as follows:
The molten steel casting meeting above-mentioned chemical composition being become continuously cast bloom or ingot casting, does not specially require the dimensions of continuously cast bloom or ingot casting, can be the ingot casting of different shape, also can be the continuously cast bloom of various thickness;
The Heating temperature of continuously cast bloom or ingot casting chooses 1100 ~ 1250 DEG C, and soaking time chooses 0.5 ~ 3h; When Heating temperature lower than 1100 DEG C or soaking time is less than 0.5h time, the center segregation of solidified structure and composition is not easily eliminated; If be added with the microalloy elements such as Nb, Ti, V in steel, its carbide not easily all dissolves, and easily causes finished product uneven microstructure; And, can make that hot rolling load is comparatively large, probability of malfunction is higher; When Heating temperature higher than 1250 DEG C or soaking time more than 3h time, organize easily thick, the raising of restriction finished product strength level; Steel slab surface oxidation is serious, and slab recovery rate is lower; Heating installation loss is serious, and energy consumption is too much;
In course of hot rolling, hot rolling start rolling temperature chooses 1050 ~ 1200 DEG C, and this temperature depends on slab heating temperature, and one is lower than slab heating temperature 50 ~ 100 DEG C; Due to initial continuously cast bloom or ingot casting thickness one be 60 ~ 200mm, hot-rolled sheet end of a period thickness one be 3 ~ 5mm, therefore, hot rolling total reduction is 92 ~ 98%.For the road number of times of hot rolling, the temperature of each passage and draft, the present invention does not explicitly call for, and can adjust flexibly according to practical situation.Temperature of hot-rolled end chooses 750 ~ 900 DEG C; When temperature of hot-rolled end is higher than 900 DEG C, steel of the present invention one can containing more austenite, in process of cooling after hot rolling, because the hardening capacity of steel of the present invention is very strong, the martensite that easy generation is more, thus, in coiling process, easily cause to batch in difficulty, hot-rolled sheet generating the problems such as tiny crack.When temperature of hot-rolled end is lower than 750 DEG C, latter stage in finishing stands, lower texturing temperature causes the softening power of matrix more weak, work hardening accumulation significantly, steel plate deformed drag is comparatively large, and finish rolling load is comparatively large, and the thickness of hot-rolled sheet and shape controlling are comparatively difficult;
After hot rolling, cool hot-rolled sheet, the present invention does not make restriction to methods for cooling, can be air cooling, also can be water-cooled.Organize after preferred cooling and be mainly ferrite and carbide, control martensite is < 30% as far as possible.If martensite content is too much, can cause coiler plate difficulty, steel plate inside generates the problems such as tiny crack.Prevent cooling rear martensite content too much, need the cooperation of temperature of hot-rolled end and rate of cooling;
After cooling, the coiling temperature of hot-rolled sheet chooses 450 ~ 650 DEG C.When coiling temperature is higher than 650 DEG C, the easy coarsening of the carbide in hot-rolled sheet, this carbide is mainly (Cr, Fe)
23c
6, when containing the microalloy elements such as Nb, Ti, V in steel, this carbide also has MC; If this carbide is thick, it not easily dissolves completely in the austenitization of cold-reduced sheet, then can reduce the C content in austenite, be unfavorable for that austenite remains to room temperature; When coiling temperature is lower than 450 DEG C, steel plate deformed drag is comparatively large, and it is lower to batch stability;
Hot-rolled sheet is annealed, and can soften, refinement and homogenizing hot rolling microstructure, then, both can reduce follow-up cold rolling load, again can refinement, the follow-up differentiation tissue of homogenizing, improve finished product comprehensive mechanical property; Annealing temperature one choose (the A of single ferrite area
c1-50) ~ (A
c1-20), avoid austenite to generate, thus avoid generating martensite after annealing cooling, then cause that cold rolling load is excessive, cold rolling microstructure is uneven; Because C, Cr content scope is comparatively large, therefore its A
c1the variation range of temperature is comparatively large, and therefore, annealing temperature is chosen at 750 ~ 950 DEG C;
The variation of annealing temperature, can cause recrystallize kinetics level to change, and then causes annealing time to there is larger variation; When annealing temperature is close to 750 DEG C, annealing time can reach ~ 8h; When annealing temperature is close to 950 DEG C, annealing time can be as short as ~ 4min.Therefore, annealing time chooses 4min ~ 8h;
As long as the pickling of hot-rolled sheet can remove hot-rolled sheet scale on surface, the chemical composition of solution used is not explicitly called for;
In cold-rolled process, because the application site of stainless steel of the present invention in automobile structure is different, different to the requirement of finished product thickness, its Cold Rolled Plate Thickness can be 0.4 ~ 2.5mm, and therefore, cold rolling total reduction chooses 40 ~ 90%;
The heat treatment process of cold-reduced sheet comprises: austenitizing, be quenched to M
s~ M
f, partition and be quenched to room temperature four-stage:
Austenitizing temperature T
achoose A
c1~ A
c5; This austenitizing comprises partial austenitizing and whole austenitizing two kinds may; Owing to adding the Cr higher than 11% in stainless steel of the present invention, high temperature austenite phase region is by severe decrease, major part C content lower than 0.05% stainless steel of the present invention, high temperature does not have single austenite phase field, only there is (austenite+ferrite) two-phase region, namely only there is the temperature A being entered (austenite+ferrite) two-phase region by single alpha ferrite phase region
c1with the temperature A being entered single delta ferrite phase region by (austenite+ferrite) two-phase region
c5, and there is not the temperature A being entered single austenite phase field by (austenite+alpha ferrite) two-phase region
c3with the temperature A being entered (austenite+delta ferrite) two-phase region by single austenite phase field
c4, in order to the mobility scale of Unify legislation austenitizing temperature, application claims A
c1< T
a< A
c5; It is emphasized that austenitizing temperature determines high temperature austenite and ferritic Phase Proportion, and this Phase Proportion can determine the intensity of finished product and the coupling of plasticity to a great extent, therefore, choosing the mechanical property of finished product of austenitizing temperature is very important;
Soaking time under austenitizing temperature chooses 0.5 ~ 10min; When soaking time is less than 0.5min, all carry out insufficient by ferrite to the dissolving of austenitic phase transformation and carbide, the C concentration of austenitic Phase Proportion and Qi Nei does not all reach stationary value, finally, can not obtain martensite and the residual austenite of q.s; When soaking time is more than 10min, high temperature austenite and ferrite crystal grain meeting coarsening, cause follow-up differentiation to organize also coarsening, thus reduce the strength level of finished product;
By austenitizing temperature T
abe quenched to temperature T
q, choose M
s< T
q< M
f, a part of austenite phase transformation can be made like this to be martensite, and a part of austenite does not undergo phase transition, for a certain amount of austenite of follow-up reservation is prepared to room temperature; Because the chemical composition change scope of steel of the present invention is comparatively large, its M
sand M
fthe variation range of temperature value is also comparatively large, therefore, and T
qthe variation range uniform requirement of value is M
s< T
q< M
f; Quenching temperature is the very crucial parameter determining residual austenite quantity, in order to obtain as far as possible many residual austenites, T
qshould not too near Ms or M
f; Work as T
qtoo close to M
stime, although most of austenite is being quenched to T
qafter do not undergo phase transition, but due to the solid solution C total amount in martensite limited, after partition, C concentration entirety in austenite is lower, and in the process being quenched to room temperature, most austenite can become martensite mutually, seldom remain to room temperature, therefore, remained austenite content is little; Work as T
qtoo close to M
ftime, most austenite is being quenched to T
qbecome martensite mutually afterwards, although after partition, the C concentration in non-transformed austenite is higher, substantially can remain after being quenched to room temperature, remained austenite content total amount also can be little;
By temperature T
abe quenched to temperature T
qrate of cooling choose 15 ~ 100 DEG C/s; One ground, in order to ensure martensitic generation, by T
ato T
qthe lower value of rate of cooling should be the critical cooling rate that martensitic transformation occurs, but, for stainless steel of the present invention, though under the rate of cooling of 1 DEG C/s, ferritic phase variable more time, also have martensitic transformation and occur; Therefore, in order to suppress ferrite transformation preferably, ensuring the generation of more martensitic transformation, choosing rate of cooling > 15 DEG C/s; But the rate of cooling being greater than 100 DEG C/s is not only difficult to realize, and easily produces inhomogeneous cooling, cause plate profile to distort and interior tissue uneven;
At temperature T
qdescend or be warming up to temperature T
pcarry out C partition, T
pvalue chooses T
q≤ T
p< 600 DEG C; Like this: on the one hand, martensitic transformation is stoped to proceed; On the other hand, can there is tempering in martensite transformation, and its inner dislocation desity suitably reduces, and its plasticity and toughness suitably improve; Again on the one hand, in martensite, super saturated solid solution C atom spreads in non-transformed austenite, improves stabilization of austenite, is beneficial to it and remains to room temperature; When the content of Si and Al of steel of the present invention is lower ((Si+Al) < 1.0%), cementite in one tempered martensite, is also had to separate out; T
pbe worth higher, the rate of diffusion of solid solution C atom is faster, and meanwhile, the precipitation rate of cementite is also faster, but both are contrary on the impact of solid solution C atom enrichment in austenite after partition; Therefore, T
pthe relativeness choosing both needs balances of value, makes the enrichment of solid solution C atom in austenite reach high level as far as possible; Work as T
pbe worth higher than 6000 time, the kinetics level that martenaging martempering and cementite are separated out all can be too high, and martensite even recrystallize occurs, and too can reduce the intensity of steel plate like this, reduce austenite and remain to room temperature; Therefore, T is chosen
q≤ T
p< 600 DEG C;
At temperature T
qunder soaking time choose 0.5 ~ 60min; When soaking time is less than 0.5min, in austenite, the enrichment of solid solution C atom is difficult to reach high level, is unfavorable for that austenite remains to room temperature, and meanwhile, martensitic tempering is also difficult to fully; When soaking time is more than 60min, in martensite, the precipitation tendency of carbide strengthens, and C atom can be suppressed to the migration do not changed in austenite by martensite, finally causes residual austenite quantity not sufficient.In actual implementation process, when the partition time by the capabilities limits of equipment must shorter time, need coordinate with higher partition temperature, reach more sufficient partition effect;
By partition temperature T
qthe rate of cooling being quenched to room temperature chooses 10 ~ 100 DEG C/s; Although the solid solution C concentration in the austenite after partition raises, it is in the process being cooled to room temperature, and one still can not all remain, and rate of cooling is beneficial to more austenite and remains to room temperature faster.As rate of cooling < 10 DEG C/s, austenite easily occurs decompose and not easily remain to room temperature; But the rate of cooling of > 100 DEG C/s is not only difficult to realize, and easily produces inhomogeneous cooling, cause plate profile to distort and interior tissue uneven.
The invention has the beneficial effects as follows:
Cr containing > 11% in chemical composition, there is good and stable solidity to corrosion, eliminate surface galvanizing, avoid that the solidity to corrosion that zinc-plated general carbon AHSS in use exists is unstable, work-ing life is short, regenerative ratio is high to Mineral resources dependency degree, long term growth by severe zinc resource restriction degree greatly, the problem such as the Composition Control difficulty of steel recycle system is large;
Substantially not containing Ni in chemical composition, material cost is significantly lower than austenitic stainless steel;
The microstructure of product, on martensite and ferritic basis, with the addition of a certain amount of residual austenite, obtains intensity, plasticity and the formability more excellent than (martensite+ferrite) dual phase steel.
Method of the present invention make use of Q & P technique, has both been conducive to obtaining above-mentioned microstructure, played again stainless steel due to the Cr contained make its hardening capacity fabulous, there is the very low advantage of the Critical cooling speed of martensitic transformation.
Accompanying drawing explanation
Fig. 1 is the automobile scanning electron microscopy macrograph figure exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet (numbering 1) of the embodiment of the present invention 1, what in figure, intra-die was level and smooth is ferrite, and what intra-die had lath-shaped texture is martensite and residual austenite.
Fig. 2 is the automobile transmission electron microscope macrograph figure exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet (numbering 1) of the embodiment of the present invention 1, in figure, (a) is the bright field image presented by transmitted light, and (b) is the dark field image presented by the diffraction light of residual austenite; What in the middle upper center of figure (a), the lower left corner and lower right field, intra-die dislocation desity was lower is ferrite; What in all the other most of regions, intra-die dislocation desity was higher is the martensite and residual austenite that are developed into by high temperature austenite, and martensite is lath-shaped, and residual austenite is the grain boundaries that film like is distributed in high temperature austenite crystal grain between martensite lath; In figure (b), region that is bright, film like is substantially for being distributed between martensite lath and the residual austenite at high temperature austenite crystal particle crystal boundary place.
Embodiment
The model of the scanning electronic microscope adopted in the embodiment of the present invention is Zeiss Ultra 55.
The model of the transmission electron microscope adopted in the embodiment of the present invention is FEI Techni G
2.
In the embodiment of the present invention, the content of residual austenite is measured by Bruker D8-advance X-ray diffractometer.
Mechanical property in the embodiment of the present invention is measured by tensile tests at room, experimental installation is Instron drawing machine, the standard of institute's foundation is GB (GB228-2010), the parallel-segment length of tension specimen is 75mm, width is 12.5mm, longitudinal extensometer gage length is 50mm, and rate of extension is 3mm/min.
A of the present invention
c1, A
c5, M
sand M
fbe measured by thermal dilatometer, thermal dilatometer model is FUJI Formastor-FII.
Illustrate by the following examples;
In each embodiment A#, B#, C#, D# and E# steel of different chemical composition and transformation temperature as shown in table 1;
Table 1
| Invention steel | A# | B# | C# | D# | E# |
| Cr | 11.8 | 11 | 17 | 12.2 | 12.5 |
| C | 0.01 | 0.025 | 0.05 | 0.03 | 0.12 |
| Mn | 0.3 | 0.35 | 0.5 | 0.2 | 0.4 |
| Si | 0.5 | 1.1 | 0.28 | 0.2 | 0.35 |
| Ni | 0.2 | / | 0.1 | 0.05 | 0.11 |
| Al | 0.005 | 0.03 | 0.006 | 0.5 | 0.01 |
| Ti | 0.18 | / | / | / | / |
| Mo | 0.08 | / | / | / | / |
| Nb | / | / | 0.18 | / | / |
| V | / | / | / | 0.19 | / |
| N | 0.006 | 0.005 | 0.04 | 0.015 | 0.02 |
| Cu | 0.01 | 0.01 | 0.02 | 0.02 | 0.02 |
| P | 0.005 | 0.01 | 0.02 | 0.02 | 0.02 |
| S | 0.001 | 0.001 | 0.001 | 0.001 | 0.002 |
| A c1 | 945 | 960 | 860 | 820 | 800 |
| A c3 | Nothing | Nothing | Nothing | Nothing | 890 |
| M s | 386 | 410 | 223 | 325 | 320 |
| M f | 294 | 280 | 90 | 165 | 110 |
Wherein A
c1, A
c3, M
sand M
ffour kinds of transformation temperature thermal dilatometers measure; At mensuration A
c1and A
c3during temperature, the temperature increasing schedule of sample is, as < 600 DEG C, temperature rise rate is 10 DEG C/
s, as > 600 DEG C, temperature rise rate is 1 DEG C/s; At mensuration M
sand M
fduring temperature, the temperature variation system of sample is, the temperature increasing schedule of sample is: when≤600 DEG C, and temperature rise rate is 10 DEG C/s, and as > 600 DEG C, temperature rise rate is 1 DEG C/s; Be warming up to 1040 DEG C (A# and B# steel) or 1000 DEG C (C#, D# and E# steel), insulation 5min, then be cooled to room temperature with the speed of 50 DEG C/s;
Embodiment 1
The manufacture method of A# steel is: smelt by set component, and continuously cast bloom is made in casting; Slab heating temperature is 1150 DEG C, soaking time is 1h; Hot rolling start rolling temperature is 1100 DEG C, and finishing temperature is 900 DEG C, and hot rolling total reduction is 92%, and coiling temperature is 650 DEG C; Hot-roll annealing temperature is 950 DEG C, soaking time is 4min; Cold rolling total reduction is 80%; Cold-reduced sheet austenitizing temperature is 1040 DEG C, soaking time is 2min, is then quickly cooled to 300 ~ 380 DEG C with the speed of 80 DEG C/s, reheats to 350 ~ 450 DEG C and is incubated 2.5 ~ 60min, being finally quickly cooled to room temperature with the speed of 100 DEG C/s; The microstructure of A# steel comprises ferrite, martensite and residual austenite, and wherein, ferritic volume fraction is 65%, and the volume fraction of residual austenite is 1 ~ 5%, and all the other are martensite;
The mechanical property of A# steel is yield strength 278 ~ 311MPa, tensile strength 498 ~ 537MPa, tension set 25.3 ~ 28.5%, strength and ductility product 12699 ~ 14763MPa%;
Concrete heat treatment process parameter and mechanical property as shown in table 2;
Table 2
Wherein in table, the implication of each symbol is:
T
a: austenitizing temperature;
T
a: the soaking time under austenitizing temperature;
T
q: quenching end temp;
T
p: partition temperature;
T
p: the soaking time under partition temperature;
R
p: yield strength, when stretching experiment shows discontinuous surrender, R
pfor the intensity that yield point elongation is corresponding, when stretching experiment shows continous way surrender, R
pfor R
p0.2;
R
mtensile strength;
A
50: gauge length is the tension set of the tension specimen of 50mm;
R
ma
50: strength and ductility product, the i.e. product of tensile strength and tension set;
N: work hardening coefficient.
Embodiment 2
The manufacture method of B# steel is: smelt by set component, and ingot casting is made in casting; Ingot casting Heating temperature is 1100 DEG C, soaking time is 1h; Hot rolling start rolling temperature is 1050 DEG C, and finishing temperature is 850 DEG C, and hot rolling total reduction is 92%, and coiling temperature is 600 DEG C; Hot-roll annealing temperature is 880 DEG C, soaking time is 10min; Cold rolling total reduction is 40%; Cold-reduced sheet austenitizing temperature is 1040 DEG C, soaking time is 2min, is then quickly cooled to 300 ~ 400 DEG C with the speed of 80 DEG C/s, reheats to 350 ~ 450 DEG C and is incubated 15 ~ 60min, being finally quickly cooled to room temperature with the speed of 100 DEG C/s; The microstructure of B# steel comprises ferrite, martensite and residual austenite, and wherein, ferritic volume fraction is 55%, and the volume fraction of residual austenite is 2 ~ 8%, and all the other are martensite;
The mechanical property of B# steel is yield strength 391 ~ 428MPa, tensile strength 668 ~ 702MPa, tension set 17.2 ~ 20.4%, strength and ductility product 12074 ~ 13628MPa%;
Concrete heat treatment process parameter and mechanical property as shown in table 3;
Table 3
The implication of each symbol is with embodiment 1.
Embodiment 3
The manufacture method of C# steel is: smelt by set component, and continuously cast bloom is made in casting; Slab heating temperature is 1200 DEG C, soaking time is 2h; Hot rolling start rolling temperature is 1150 DEG C, and finishing temperature is 800 DEG C, and hot rolling total reduction is 95%, and coiling temperature is 500 DEG C; Hot-roll annealing temperature is 800 DEG C, soaking time is 8h; Cold rolling total reduction is 75%; Cold-reduced sheet austenitizing temperature is 1000 DEG C, soaking time is 2min, is then quickly cooled to 100 ~ 200 DEG C with the speed of 20 DEG C/s, reheats to 450 ~ 575 DEG C and is incubated 1 ~ 60min, being finally quickly cooled to room temperature with the speed of 20 DEG C/s;
The microstructure of C# steel comprises ferrite, martensite and residual austenite, and wherein ferritic volume fraction is 55%, and the volume fraction of residual austenite is 2 ~ 12%, and all the other are martensite;
The mechanical property of C# steel is yield strength 392 ~ 416MPa, tensile strength 707 ~ 740MPa, tension set 25.0 ~ 27.9%, strength and ductility product 18500 ~ 19778MPa%;
Concrete heat treatment process parameter and mechanical property as shown in table 4;
Table 4
The implication of each symbol is with embodiment 1.
Embodiment 4
The manufacture method of D# steel is: smelt by set component, and continuously cast bloom is made in casting; Slab heating temperature is 1200 DEG C, soaking time is 2.5h; Hot rolling start rolling temperature is 1150 DEG C, and finishing temperature is 800 DEG C, and hot rolling total reduction is 98%, and coiling temperature is 500 DEG C; Hot-roll annealing temperature is 800 DEG C, soaking time is 8h; Cold rolling total reduction is 75%; Cold-reduced sheet austenitizing temperature is 1000 DEG C, soaking time is 2min, is then quickly cooled to 180 ~ 300 DEG C with the speed of 20 DEG C/s, reheats to 450 ~ 575 DEG C and is incubated 1 ~ 60min, being finally quickly cooled to room temperature with the speed of 20 DEG C/s;
The microstructure of D# steel comprises ferrite, martensite and residual austenite, and wherein ferritic volume fraction is 27%, and the volume fraction of residual austenite is 2 ~ 9%, and all the other are martensite;
The mechanical property of D# steel is yield strength 530 ~ 604MPa, tensile strength 825 ~ 857MPa, tension set 15.5 ~ 18.7%, strength and ductility product 13801 ~ 15577MPa%;
Concrete heat treatment process parameter and mechanical property as shown in table 5;
Table 5
The implication of each symbol is with embodiment 1.
Embodiment 5
The manufacture method of E# steel is: smelt by set component, and continuously cast bloom is made in casting; Slab heating temperature is 1250 DEG C, soaking time is 0.5h; Hot rolling start rolling temperature is 1200 DEG C, and finishing temperature is 750 DEG C, and hot rolling total reduction is 98%, and coiling temperature is 450 DEG C; Hot-roll annealing temperature is 750 DEG C, soaking time is 8h; Cold rolling total reduction is 90%; Cold-reduced sheet austenitizing temperature is 1000 DEG C, soaking time is 2min, is then quickly cooled to 125 ~ 300 DEG C with the speed of 15 DEG C/s, reheats to 450 ~ 575 DEG C and is incubated 1 ~ 60min, being finally quickly cooled to room temperature with the speed of 15 DEG C/s;
The microstructure of E# steel is not containing ferrite, and only comprise martensite and residual austenite, wherein the volume fraction of residual austenite is 3 ~ 15%, and all the other are martensite;
The mechanical property of E# steel is yield strength 792 ~ 872MPa, tensile strength 1205 ~ 1282MPa, tension set 17.7 ~ 22.3%, strength and ductility product 22691 ~ 27429MPa%;
Concrete heat treatment process parameter and mechanical property as shown in table 6;
Table 6
The implication of each symbol is with embodiment 1.
Claims (4)
1. an automobile is with exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet, it is characterized in that composition by weight percentage containing Cr11.0 ~ 17.0%, C 0.01 ~ 0.12%, Mn 0.2 ~ 0.5%, Si 0.2 ~ 1.1%, Al 0.005 ~ 0.5%, Ni < 0.3%, Nb < 0.2%, Ti < 0.2%, V < 0.2%, Mo < 0.1%, Cu < 0.03%, N < 0.05%, P < 0.03%, S < 0.003%, surplus is Fe.
2. automobile according to claim 1 is with exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet, it is characterized in that the yield strength of this stainless steel plate is 280 ~ 870MPa, tensile strength is 500 ~ 1280MPa, and tension set is 15.5 ~ 29.0%, strength and ductility product 12000 ~ 27500MPa%.
3. automobile according to claim 1 is with exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet, it is characterized in that in the tissue of this stainless steel plate, and the volume fraction of residual austenite is 1 ~ 15%, and ferritic volume fraction is 0 ~ 65%, and all the other are martensite.
4. the automobile according to claim 1 manufacture method exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet, is characterized in that carrying out according to the following steps:
(1) cast: smelt by set component, and ingot casting or continuously cast bloom are made in casting;
(2) hot rolling: ingot casting or continuously cast bloom are heated to 1100 ~ 1250 DEG C, insulation 0.5 ~ 3h, then carries out hot rolling, start rolling temperature is 1050 ~ 1200 DEG C, and finishing temperature is 750 ~ 900 DEG C, and hot rolling total reduction is 92 ~ 98%, finally batch at 450 ~ 650 DEG C, obtain hot-rolled steel sheet;
(3) cold rolling: to be annealed by hot-rolled steel sheet, annealing temperature is 750 ~ 950 DEG C, and the time is 4min ~ 480min, then be cooled to normal temperature, pickling removing hot-rolled sheet scale on surface, then carry out cold rolling, cold rolling total reduction is 40 ~ 90%, obtains cold-rolled steel sheet;
(4) thermal treatment:
(4.1) cold-rolled steel sheet is heated to temperature T
a, insulation 0.5 ~ 10min carries out austenitizing; Wherein A
c1< T
a< A
c5, described A
c1for the temperature that tissue is austenite+ferrite two-phase by single alpha ferrite phase in version, described A
c5for organizing the temperature being changed into single delta ferrite phase by austenite+ferrite two-phase;
(4.2) then cold-rolled steel sheet is cooled to temperature T with the rate of cooling of 15 ~ 100 DEG C/s
q, make austenite fraction become martensite mutually; Wherein M
s< T
q< M
f, described M
sfor tissue by austenite to temperature martensitic transformation, described M
ffor tissue is by the end temp of austenite to martensitic transformation;
(4.3) again cold-rolled steel sheet is warming up to temperature T
p, insulation 0.5 ~ 60min carries out C partition; Wherein T
q≤ T
p< 600 DEG C;
(4.4) finally cold-rolled steel sheet being cooled to room temperature with the rate of cooling of 10 ~ 100 DEG C/s, obtaining automobile with exempting from zinc-plated high strength and plasticity cold rolled stainless steel sheet.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510005588.4A CN104532129B (en) | 2015-01-06 | 2015-01-06 | Galvanization-free high-strength and plasticity cold-rolled stainless steel plate for automobile and manufacturing method of galvanization-free high-strength and plasticity cold-rolled stainless steel plate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510005588.4A CN104532129B (en) | 2015-01-06 | 2015-01-06 | Galvanization-free high-strength and plasticity cold-rolled stainless steel plate for automobile and manufacturing method of galvanization-free high-strength and plasticity cold-rolled stainless steel plate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104532129A true CN104532129A (en) | 2015-04-22 |
| CN104532129B CN104532129B (en) | 2017-02-22 |
Family
ID=52847744
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510005588.4A Expired - Fee Related CN104532129B (en) | 2015-01-06 | 2015-01-06 | Galvanization-free high-strength and plasticity cold-rolled stainless steel plate for automobile and manufacturing method of galvanization-free high-strength and plasticity cold-rolled stainless steel plate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104532129B (en) |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104789744A (en) * | 2015-05-16 | 2015-07-22 | 王文姣 | Heat treatment method of high-strength automobile frame |
| CN104928596A (en) * | 2015-05-16 | 2015-09-23 | 王文姣 | High-strength automobile frame and manufacturing method thereof |
| CN106256920A (en) * | 2015-06-17 | 2016-12-28 | 宝钢不锈钢有限公司 | A kind of titanium-containing austenitic stainless steel with good oxidation resistance energy and manufacture method thereof |
| CN106591736A (en) * | 2016-12-13 | 2017-04-26 | 山西太钢不锈钢股份有限公司 | High-strength low-chromium stainless steel and heat treatment method thereof |
| CN107554291A (en) * | 2016-06-30 | 2018-01-09 | 宁波高发汽车控制系统股份有限公司 | Electron accelerator pedal assembly |
| CN108677107A (en) * | 2018-06-20 | 2018-10-19 | 上海铭客传动系统有限公司 | A kind of stainless steel used for conveyer belt and its technology of preparing |
| CN109435650A (en) * | 2018-11-21 | 2019-03-08 | 宁波精乐汽车部件有限公司 | A kind of automobile front door window frame |
| CN110088326A (en) * | 2016-12-14 | 2019-08-02 | 蒂森克虏伯钢铁欧洲股份公司 | Flat hot rolled bar product and its production method |
| WO2019176283A1 (en) * | 2018-03-15 | 2019-09-19 | 日鉄ステンレス株式会社 | Martensitic stainless steel sheet, method for manufacturing same, and spring member |
| CN111315908A (en) * | 2017-11-10 | 2020-06-19 | 安赛乐米塔尔公司 | Cold-rolled steel sheet and method for producing same |
| CN114807589A (en) * | 2022-03-31 | 2022-07-29 | 中钢集团邢台机械轧辊有限公司 | Martensite-bainite complex phase structure heat treatment control method of high-carbon high-speed steel |
| CN115181898A (en) * | 2021-04-02 | 2022-10-14 | 宝山钢铁股份有限公司 | 1280 MPa-grade low-carbon low-alloy Q & P steel and rapid thermal treatment manufacturing method thereof |
| CN117737372A (en) * | 2024-02-19 | 2024-03-22 | 太原科技大学 | 2.0 GPa-grade Cu-containing hot-formed steel plate and preparation method thereof |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108707819B (en) * | 2018-05-16 | 2020-01-24 | 中北大学 | High-performance steel containing delta ferrite and preparation method thereof |
-
2015
- 2015-01-06 CN CN201510005588.4A patent/CN104532129B/en not_active Expired - Fee Related
Non-Patent Citations (2)
| Title |
|---|
| 谢胜涛等: "热轧工艺对409L铁素体不锈钢深冲性的影响", 《东北大学学报（自然科学版）》 * |
| 谢胜涛等: "高性能节约型不锈钢制备技术研发与应用", 《中国工程科学》 * |
Cited By (24)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104789744A (en) * | 2015-05-16 | 2015-07-22 | 王文姣 | Heat treatment method of high-strength automobile frame |
| CN104928596A (en) * | 2015-05-16 | 2015-09-23 | 王文姣 | High-strength automobile frame and manufacturing method thereof |
| CN106256920A (en) * | 2015-06-17 | 2016-12-28 | 宝钢不锈钢有限公司 | A kind of titanium-containing austenitic stainless steel with good oxidation resistance energy and manufacture method thereof |
| CN107554291B (en) * | 2016-06-30 | 2020-12-29 | 宁波高发汽车控制系统股份有限公司 | Electronic accelerator pedal assembly |
| CN107554291A (en) * | 2016-06-30 | 2018-01-09 | 宁波高发汽车控制系统股份有限公司 | Electron accelerator pedal assembly |
| CN106591736A (en) * | 2016-12-13 | 2017-04-26 | 山西太钢不锈钢股份有限公司 | High-strength low-chromium stainless steel and heat treatment method thereof |
| US11371113B2 (en) | 2016-12-14 | 2022-06-28 | Evonik Operations Gmbh | Hot-rolled flat steel product and method for the production thereof |
| CN110088326A (en) * | 2016-12-14 | 2019-08-02 | 蒂森克虏伯钢铁欧洲股份公司 | Flat hot rolled bar product and its production method |
| CN110088326B (en) * | 2016-12-14 | 2022-06-24 | 蒂森克虏伯钢铁欧洲股份公司 | Hot-rolled flat steel product and method for the production thereof |
| CN111315908A (en) * | 2017-11-10 | 2020-06-19 | 安赛乐米塔尔公司 | Cold-rolled steel sheet and method for producing same |
| US11920207B2 (en) | 2017-11-10 | 2024-03-05 | Arcelormittal | Cold rolled steel sheet and a method of manufacturing thereof |
| JP2019157229A (en) * | 2018-03-15 | 2019-09-19 | 日鉄日新製鋼株式会社 | Martensitic stainless steel sheet and method of producing the same, and spring member |
| CN111727269A (en) * | 2018-03-15 | 2020-09-29 | 日铁不锈钢株式会社 | Martensitic stainless steel sheet, method for producing same, and spring member |
| US11499204B2 (en) | 2018-03-15 | 2022-11-15 | Nippon Steel Stainless Steel Corporation | Martensitic stainless steel sheet, method for manufacturing same, and spring member |
| CN111727269B (en) * | 2018-03-15 | 2021-11-23 | 日铁不锈钢株式会社 | Martensitic stainless steel sheet, method for producing same, and spring member |
| JP7049142B2 (en) | 2018-03-15 | 2022-04-06 | 日鉄ステンレス株式会社 | Martensitic stainless steel sheet and its manufacturing method and spring members |
| WO2019176283A1 (en) * | 2018-03-15 | 2019-09-19 | 日鉄ステンレス株式会社 | Martensitic stainless steel sheet, method for manufacturing same, and spring member |
| CN108677107A (en) * | 2018-06-20 | 2018-10-19 | 上海铭客传动系统有限公司 | A kind of stainless steel used for conveyer belt and its technology of preparing |
| CN109435650A (en) * | 2018-11-21 | 2019-03-08 | 宁波精乐汽车部件有限公司 | A kind of automobile front door window frame |
| CN115181898A (en) * | 2021-04-02 | 2022-10-14 | 宝山钢铁股份有限公司 | 1280 MPa-grade low-carbon low-alloy Q & P steel and rapid thermal treatment manufacturing method thereof |
| CN115181898B (en) * | 2021-04-02 | 2023-10-13 | 宝山钢铁股份有限公司 | 1280 MPa-level low-carbon low-alloy Q & P steel and rapid heat treatment manufacturing method thereof |
| CN114807589A (en) * | 2022-03-31 | 2022-07-29 | 中钢集团邢台机械轧辊有限公司 | Martensite-bainite complex phase structure heat treatment control method of high-carbon high-speed steel |
| CN117737372A (en) * | 2024-02-19 | 2024-03-22 | 太原科技大学 | 2.0 GPa-grade Cu-containing hot-formed steel plate and preparation method thereof |
| CN117737372B (en) * | 2024-02-19 | 2024-04-16 | 太原科技大学 | 2.0 GPa-grade Cu-containing hot-formed steel plate and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104532129B (en) | 2017-02-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104532129B (en) | Galvanization-free high-strength and plasticity cold-rolled stainless steel plate for automobile and manufacturing method of galvanization-free high-strength and plasticity cold-rolled stainless steel plate | |
| CN111440996B (en) | 6-8 mm TMCP (thermal mechanical control processing) on-line quenching low-yield-ratio high-strength wear-resistant steel NM400 coiled plate and production method thereof | |
| CN102046827B (en) | Method for manufacturing very high strength, cold-rolled, dual phase steel sheets, and sheets thus produced | |
| CN100439543C (en) | Hot-rolled super-strength martensitic steel and method for manufacturing same | |
| CN102586688B (en) | A kind of dual phase sheet steel and manufacture method thereof | |
| CN102839329B (en) | Cold-rolling double-phase-steel steel plate with tensile strength of 450 MPa, and preparation method thereof | |
| CN103882330B (en) | A kind of low yield strength ratio superhigh intensity non-quenched and tempered steel plate and production method thereof | |
| CN113416890B (en) | High-hole-expansion high-plasticity 980 MPa-grade cold-rolled continuous annealing steel plate and preparation method thereof | |
| CN113388779B (en) | 1.5 GPa-grade ultrahigh-strength high-plasticity high-hole-expansion DH steel plate and preparation method thereof | |
| CN102174685B (en) | 800 MPa grade cold-rolling dual-phase steel and manufacturing method thereof | |
| CN103562417A (en) | Method for the production of very-high-strength martensitic steel and sheet or part thus obtained | |
| CN105441805B (en) | A kind of 800MPa grades of car Galvanized Dual Phase Steel and production method | |
| CN105369135B (en) | A kind of 450MPa levels car Galvanized Dual Phase Steel and production method | |
| CN110088336B (en) | High-strength steel sheet having excellent high-temperature elongation properties, warm-press-formed member, and methods for producing these | |
| CN103361560A (en) | Cold-rolled hot-molded steel plate and production method thereof | |
| CN102719732A (en) | Hot-rolled high-strength dual phase steel plate and manufacturing method thereof | |
| CN104513927A (en) | High-strength high-rigidity steel plate with tensile strength of 800 MPa and preparation method thereof | |
| CN105803334B (en) | Tensile strength 700MPa level hot rolling Multiphase Steels and its production method | |
| CN113403550B (en) | High-plasticity fatigue-resistant cold-rolled hot-galvanized DH1180 steel plate and preparation method thereof | |
| CN113416889B (en) | Ultrahigh-strength hot-galvanized DH1470 steel with good welding performance and preparation method thereof | |
| CN105401071B (en) | A kind of 500MPa levels car Galvanized Dual Phase Steel and production method | |
| CN101353755B (en) | High tensile strength substrate, hot dip galvanizing automobile exterior panel and manufacturing method thereof | |
| CN113403551B (en) | High-yield-ratio hydrogen embrittlement-resistant cold-rolled DH980 steel plate and preparation method thereof | |
| CN106498296A (en) | A kind of manufacture method of yield strength 1100MPa level high-strength steel | |
| CN110129673A (en) | A kind of 800MPa grades of high strength and ductility Q&P steel plate and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20170222 |