CN104264052B - A kind of steel for engineering machinery plate and production method thereof - Google Patents

A kind of steel for engineering machinery plate and production method thereof Download PDF

Info

Publication number
CN104264052B
CN104264052B CN201410593263.8A CN201410593263A CN104264052B CN 104264052 B CN104264052 B CN 104264052B CN 201410593263 A CN201410593263 A CN 201410593263A CN 104264052 B CN104264052 B CN 104264052B
Authority
CN
China
Prior art keywords
steel
steel plate
plate
temperature
production
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.)
Active
Application number
CN201410593263.8A
Other languages
Chinese (zh)
Other versions
CN104264052A (en
Inventor
曾斌
王慎德
廖志
肖尊湖
刘建华
肖爱达
徐刚军
杨志刚
周明伟
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Lysteel Co Ltd
Original Assignee
Lysteel Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Lysteel Co Ltd filed Critical Lysteel Co Ltd
Priority to CN201410593263.8A priority Critical patent/CN104264052B/en
Publication of CN104264052A publication Critical patent/CN104264052A/en
Application granted granted Critical
Publication of CN104264052B publication Critical patent/CN104264052B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Abstract

The invention discloses a kind of steel for engineering machinery plate and production method thereof, the chemical composition weight/mass percentage composition of steel plate is: C 0.05 ~ 0.09, Si 0.05 ~ 0.30, Mn 1.5 ~ 2.0, P≤0.025, S≤0.005, Nb 0 ~ 0.07, Ti 0.08 ~ 0.15, Mo 0.10 ~ 0.30, Als 0.015 ~ 0.06, Ca 0.0010 ~ 0.0030, N≤0.006, surplus are Fe, and steel plate thickness is 3.0mm ~ 8.5mm.The present invention uses the ultrafast cool equipment of advanced person and domestic unique 2250mm wide flat steel heat-treatment lines to produce, its intensity and elongation percentage are more than needed big, impact flexibility is good, it is little that postwelding loses strong rate, especially show as that steel plate anisotropy angle value little, uneven is little, buckling performance is superior, be suitable for manufacturing the arm of the engineering machinery vehicles such as crane.

Description

A kind of steel for engineering machinery plate and production method thereof
Technical field
The present invention relates to high-strength high-toughness steel plate and production method thereof that a kind of yield strength is 700MPa level, especially relate to And it is a kind of for engineering machinery arm steel plate and production methods thereof such as cranes.
Background technology
Light-weight design has been widely used in Space Science and Technology, automobile, electronic industry, but engineering machinery vehicle neck at home Territory, for crane, this field still belongs to the starting stage.Realize crane core component arm Lightweight, can significantly reduce the workload of crane, improves rated power, it is achieved the leap of equipment performance.Use has good Good mechanical property and the high-strength high-toughness steel plate of serviceability, can alleviate the weight of crane arm well, it is achieved Light-weighted target.
For the main technical requirements bag that high-level large-tonnage yield strength is 700MPa level crane arm steel Include: (1) steel plate thickness specification is mainly at 4 ~ 8mm;(2) mechanical property: yield strength (Rel/Rp0.2) >=700MPa, tension is strong Degree (Rm) >=785MPa, elongation after fracture (A) >=15% ,-20 DEG C of ballistic work (Akv) >=40J, 2 times of bending moment bendings 180 ° are qualified; (3) plate shape require: glacing flatness need to control at below 3mm/m, otherwise, after die mould arm part easily occur U-type groove both sides the most contour, Asymmetric, and lower arch the defect such as upwarps;(4) steel plate serviceability: good (the lap joint CTS weld crack rate of welding performance ≤ 3%, deposited strength >=750MPa), buckling performance is superior, and (without specific targets, current domestic steel plate once checks the qualification rate to be 60 ~ 70%).
Based on the crane arm reason of steel thickness specification, steel plate is nearly all by conventional hot continuous rolling machine production line next life Produce.Production technology includes TMCP(controlled rolling and controlled cooling) and quenched (quenching+tempering) two kinds, wherein TMCP technology is because operation is shorter, Production cost is relatively low, and the delivery cycle is short, and the most all of roll bending manufacturing firm is used, and only minority technology is the most advanced Steel mill, use and roll the quenched mode of rear press quenching+tempering to produce this kind of crane arm 700MPa level steel, represent product The WELDOX 700 of SSAB company of Pin You Sweden.
The patent application of Application No. 200910083635.1 proposes the life of a kind of high-strength steel with yield strength of 700 MPa Product method.Production method in this patent, owing to continuous casting and rolling slab thickness is generally 60 ~ 90mm, the total reduction of milling train is little, And using the highest section cooling of cooling rate, these factors make the surplus capacity of properties of product little, and especially impact flexibility is the most inclined Low.It addition, patent application for product be hot rolled coil.
The patent application of Application No. 201110366129.0 proposes the hot rolling more than 700 MPa levels of a kind of yield strength Titaniferous high strength steel plate and manufacture method thereof.This type of steel relies primarily on the precipitation strength of high Ti content to improve intensity, because Ti compares Active, easily aoxidize during smelting molten steel, and be combined with N, S and lose its effect that super-refinement separates out in ferrite Really, therefore intensity relative fluctuation is big.And Ti content is the highest, its low-temperature impact toughness declines more obvious, impact easily occurs The underproof situation of merit.3rd, this patent application for product be hot rolled coil.
The patent application of Application No. 201010101815.0 proposes a kind of low cost non-tune of yield strength 700MPa level Matter processes high strength steel plate and manufacture method thereof, and this type of steel uses the composition design of low C-Si-Mn-Nb-Ti-Cr, uses in composition Cr and do not use Mo as quenching degree element.Using compared with Mo with Cr, the carbide stability that both are formed has significant difference, The temper resistance using Mo is the highest, and obvious intensity will not be brought to decline, and therefore, these type of 700 MPa steel adding Cr are suitableeer Deliver goods together in hot-rolled state.It addition, product described in this patent is also hot rolled coil.
The patent application of Application No. 201110343384.3 proposes a kind of 750MPa~880MPa level vehicle with high-strength Steel and production method thereof, its patent application for for hot rolled coil product.
It is high-strength that the patent application of Application No. 201010186720.3 proposes a kind of economical yield strength 690MPa level Steel plate and manufacture method thereof, the patent application of Application No. 201210209649.5 proposes a kind of without the surrender of nickel high tenacity 700MPa level high-strength steel and manufacture method thereof, the patent application of Application No. 201310269680.2 proposes a kind of tension 800MPa level hydropower station pressure pipeline high strength steel plate and production method.The cut deal that is involved by aforementioned three patent applications produces Product.
The problem that prior art exists is: more steel enterprise is limited by the restriction of cooling device, and roller repairing speed is slow so that Intensity is little with low-temperature impact work value surplus capacity.It addition, other steel mill domestic is because lacking wide flat steel heat-treatment production line, all use heat Roll the crosscutting plate after the crosscutting plate of volume or hot rolled coil slow cooling self tempering or the crosscutting plate after hot rolled coil bell-type annealing is delivered goods, open Steel plate internal stress after Ping eliminates not thorough, and plate shape glacing flatness is the highest, so that the arm die mould that impact is follow-up.
Summary of the invention
It is an object of the invention to provide a kind of yield strength being applicable to crane lightweight requirements is 700MPa level Steel for engineering machinery (especially crane arm steel) and production method thereof.
For achieving the above object, the technical solution used in the present invention is:
The described quality plate that a kind of yield strength is 700MPa level, its chemical composition (weight/mass percentage composition) is: C 0.05~0.09、Si 0.05~0.30、Mn 1.5~2.0、P≤0.025、S≤0.005、Nb 0~0.07、Ti 0.08~0.15、Mo 0.10 ~ 0.30, Als 0.015 ~ 0.06, Ca 0.0010 ~ 0.0030, N≤0.006, surplus is Fe, steel plate thickness be 3.0mm ~ 8.5mm。
The production method of described a kind of steel for engineering machinery plate, comprises the technical steps that:
Converter or electric furnace smelting → LF+RH refine → continuous casting → heating furnace heating → roughing → finish rolling → ultrafast cold → laminar flow Cool down → batch → cross section is flat → tempering heat treatment, technological parameter is as follows:
(1) continuous casting steel billet use hot-loading and hot-conveying technique, it is ensured that slab enter heating furnace time charging temperature 300 DEG C with On, slab heating temperature more than 1200 DEG C.
(2) hot rolling finishing temperature controls at 820 ~ 880 DEG C.
(3) cooling facility for laminar flow using the cooling rate fast cooling device more than 25 DEG C/s or encryption after rolling cools down.
(4) oiler temperature control is at 560 ~ 640 DEG C.
(5) steel plate through open gentle crosscutting after, heat-treatment lines carry out temperature be 550 ~ 650 DEG C, the time be 10 ~ 50min's Tempering.
Use a kind of steel for engineering machinery plate and production method thereof provided such as technique scheme, with prior art phase Ratio, has the technical effect that
(1) winding off the crosscutting plate of Heisei hot rolling by hot rolling, the most unique 2250mm wide flat steel heat-treatment lines enters Row tempering heat treatment.
(2) Q690D, EN 10149-2 in HR700F, GB/T 16270 during mechanical property of steel plate meets GB/T 20887.1 The mechanical property requirements of middle S700MC, performance requirement is: yield strength be more than 700MPa, tensile strength be more than 785MPa ,-20 DEG C Ballistic work is more than 40J, and elongation percentage is more than 15%, and it is qualified that cold-bending property meets 2 times of moments of flexure bendings 180 °.
(3) in addition to the technology meeting existing yield strength 700MPa level steel for engineering machinery requires, its mechanical property is rich Surplus foot, it is low, especially because steel plate property anisotropy is little, glacing flatness is high, buckling performance is superior so that crane that postwelding loses strong rate Manufacturer improves the utilization rate of steel plate, decreases arm part fire school, strikes the links such as school, improves production efficiency.This The performance indications of bright steel are concrete such as: yield strength >=800MPa, tensile strength >=850MPa, elongation percentage >=18% ,-20 DEG C of impacts Merit >=80J, the 180 ° of bendings of 2 times of bending moments of clod wash are qualified, steel plate unevenness≤2mm/m, and strong rate < 10% is lost in welding, respectively to poor performance Different little, steel plate internal stress is little, and buckling performance once checks qualification rate > 90%, exceeds about 30% than other producer's product.
(4) steel of the present invention is also applied for other parts of engineering machinery vehicle, such as concrete mixer arm, concrete mixer car Body, the position such as crane vehicle body, base plate.
Detailed description of the invention
Below in conjunction with embodiment, the detailed description of the invention of the present invention is further described.
Described steel plate, its chemical composition weight/mass percentage composition is: C 0.05 ~ 0.09, Si 0.05 ~ 0.30, Mn 1.5 ~ 2.0、P≤0.025、S≤0.005、Nb 0~0.07、Ti 0.08~0.15、Mo 0.10~0.30、Als 0.015~0.06、Ca 0.0010 ~ 0.0030, N≤0.006, surplus is Fe, and the thickness of steel plate is 3.0mm ~ 8.5mm.
Described steel plate uses the composition design of low C, high Mn, middle Nb, high Ti, low Mo, is sent by steel slab heat and guarantees The quality problems such as slab not crack initiation not fracture.The organization type of steel plate of the present invention tempering state is polygonal ferrite+a small amount of Cementite tissue.It is tempered by hot rolled steel plate, on the one hand plays the precipitation-hardening effect of Ti, Nb, Mo element further, to improve Intensity, on the other hand, steel plate tempering can eliminate internal stress, it is ensured that plate shape, thus meets crane arm to bending The high request of energy.In composition, each element Main Function is as follows: (1) C: low carbon content, reduces carbon equivalent to improve the welding of steel plate Performance, meanwhile, appropriate C Yu Ti, Nb, Mo form stable MC two-phase precipitate, increase substantially intensity;(2) Si: solid solution is strong Changing element, for being used as to need the parts of coating, for improving coating performance, Si content can be controlled by lower limit, such as 0.06%, right In being used as the parts without coating requirement, Si content can suitably increase, but as far as possible less than 0.3%, more to prevent top layer from being formed SiO2Product;(3) Mn: solution strengthening improves intensity, it addition, non-recrystallization temperature when high Mn content can improve hot rolling, fills Dividing utilizes the austenite flattening of finish rolling section to carry out crystal grain thinning;(4) S: control to below 50ppm as far as possible, thus improve effective Ti Ratio in full Ti;(5) P: for cyrystal boundary segregation element, the low-temperature impact toughness of steel plate can be reduced, but P content is less than During 0.02wt.%, Toughness is impacted for this hot rolling and tempering state steel plate little;(6) Ti;Strong precipitation strength element, energy Become TiC super-refinement nano-scaled precipitate with C-shaped, separate out in ferrite, increase substantially intensity;(7) Nb: important crystal grain thinning Element, additionally plays certain precipitating reinforcing effect;(8) Mo: be on the one hand quenching degree element, promote quasi-polygonal ferrite Being formed, on the other hand, form compound Second Phase Precipitation thing (Ti, Mo) C with TiC, during tempering, precipitate will not be grown up rapidly, tool There is good temper resistance.
Described Plate Production method, comprises the technical steps that:
Converter or electric furnace smelting → LF+RH refine → continuous casting → heating furnace heating → roughing → finish rolling → ultrafast cold → laminar flow Cool down → batch → cross section is flat → tempering heat treatment, technological parameter is as follows:
(1) continuous casting steel billet use hot-loading and hot-conveying technique, it is ensured that slab enter heating furnace time charging temperature 300 DEG C with On, slab heating temperature more than 1200 DEG C.
(2) hot rolling finishing temperature controls at 820 ~ 880 DEG C.
(3) cooling facility for laminar flow using the cooling rate fast cooling device more than 25 DEG C/s or encryption after rolling cools down.
(4) oiler temperature control is at 560 ~ 640 DEG C.
(5) steel plate through open gentle crosscutting after, heat-treatment lines carry out temperature be 550 ~ 650 DEG C, the time be 10 ~ 50min's Tempering.
Embodiment 1
At slab caster, smelting in 210 tons of converters the molten steel through LF stove Yu RH stove refine are poured into strand, and it is changed Learning composition quality percentage composition is: C 0.076, Si 0.21, Mn 1.81, P 0.011, S 0.0017, Als 0.032, Ca 0.0005, Nb 0.060, Ti 0.101, Mo 0.19, remaining is Fe and inevitable impurity.
Slab thickness is 230 mm, rolls at 2250 conventional hot continuous rolling machine production lines, and heating-up temperature is 1240 DEG C, finish rolling Inlet temperature is 1060 DEG C, and workpiece thickness is 46mm, and finishing temperature is 850 DEG C, and target thickness is 4mm, through ultrafast cold after rolling Cold with ACC layer being cooled to target coiling temperature 600 DEG C, coil of strip batches rear air cooling.After steel roll temperature is less than 60 DEG C, can be by coil of strip Carry out out at traverse flat, open plain plate and carry out 650 DEG C × 25min tempering one by one at wide flat steel heat-treatment lines.
The high-strength steel with yield strength of 700 MPa produced according to above method, steel plate flatness can ensure at below 2mm/m. Steel plate is from top layer to center, and crystallite dimension is the most tiny, and size is highly uniform, and average grain size is 3-5 μm, microscopic structure class Type is quasi-polygonal ferrite+a small amount of cementite.Described steel plate and hot rolling raw material plate thereof and other patent identical grade of steel product Mechanical property compare and be shown in Table 1.
Table 1 example 1 mechanical property and the comparison with other steel
From table 1 it follows that this patent tempered steel is compared with other steel of same intensity rank, yield strength is the highest Going out 75MPa, tensile strength at least exceeds 51MPa, and plasticity index is no worse than other steel.It addition, horizontal, longitudinal mechanical property difference Less than its hot rolling raw steel, steel plate is respectively to performance evenly, more stable.
Embodiment 2
At slab caster, smelting in 210 tons of converters the molten steel through LF stove Yu RH stove refine are poured into strand, and it is changed Learning composition quality percentage composition is: C 0.073, Si 0.26, Mn 1.82, P 0.012, S 0.0029, Als 0.029, Ca 0.0005, Nb 0.063, Ti 0.116, Mo 0.18, remaining is Fe and inevitable impurity.
Slab thickness is 230 mm, rolls at 2250 conventional hot continuous rolling machine production lines, and heating-up temperature is 1240 DEG C, finish rolling Inlet temperature is 1030 DEG C, and workpiece thickness is 51mm, and finishing temperature is 850 DEG C, and target thickness is 6mm, through ultrafast cold after rolling Cold with ACC layer being cooled to target coiling temperature 600 DEG C, coil of strip batches rear air cooling.After steel roll temperature is less than 60 DEG C, can be by coil of strip Carry out out at traverse flat, open plain plate and carry out 650 DEG C × 25min tempering one by one at thin plate heat-treatment lines.
The high-strength steel with yield strength of 700 MPa produced according to above method, steel plate flatness can ensure at below 2mm/m. Steel plate average grain size is 4-6 μm, and size is highly uniform, and microscopic structure type is quasi-polygonal ferrite+a small amount of cementite. The mechanical property of described steel plate and hot rolling raw material plate and other patent identical grade of steel product compares and is shown in Table 2.
Table 2 example 2 mechanical property and the comparison with other steel
From Table 2, it can be seen that tempering steel plate is compared with other steel of same intensity rank, yield strength at least exceeds 45MPa, tensile strength at least exceeds 20MPa, and plasticity index and impact flexibility are no worse than other steel.It addition, horizontal, longitudinal performance Its hot rolling raw steel of diversity ratio is little, and steel plate is respectively to performance evenly, more stable.
Embodiment 3
Smelting in 210 tons of converters the molten steel through LF stove Yu RH stove refine are poured into strand at slab caster, its matter Amount percentage composition be: C 0.068, Si 0. 0.21, Mn 1.87, P 0.013, S 0.0022, Als 0.034, Ca 0.0008, Nb 0.061, Ti 0.109, Mo 0.19, remaining is Fe and inevitable impurity.
Slab thickness is 230 mm, rolls at 2250 conventional hot continuous rolling machine production lines, and heating-up temperature is 1240 DEG C, finish rolling Inlet temperature is 1030 DEG C, and workpiece thickness is 54mm, and finishing temperature is 840 DEG C, and target thickness is 8mm, through ultrafast cold after rolling Cold with ACC layer being cooled to target coiling temperature 580 DEG C, coil of strip batches rear air cooling.After steel roll temperature is less than 60 DEG C, coil of strip is existed Traverse carries out out flat, opens plain plate and carries out 650 DEG C × 30min tempering one by one at thin plate heat-treatment lines.
The high-strength steel with yield strength of 700 MPa produced according to above method, steel plate flatness can ensure at below 2mm/m. Steel plate average grain size is 4-6 μm, and size is highly uniform, and microscopic structure type is quasi-polygonal ferrite+a small amount of cementite. The mechanical property of described steel plate and hot rolling raw material plate and other patent identical grade of steel product compares and is shown in Table 3.
Table 3 example 3 mechanical property and the comparison with other steel
From table 3 it is observed that tempering steel plate is compared with other steel of same intensity rank, yield strength at least exceeds 77MPa, tensile strength at least exceeds 69MPa, and plasticity is suitable with other steel with toughness aggregative indicator.It addition, horizontal, longitudinal performance Its hot rolling raw steel of diversity ratio is little, and steel plate is respectively to performance evenly, more stable.

Claims (1)

1. the production method of a steel for engineering machinery plate, it is characterised in that: steel plate chemical composition weight/mass percentage composition is C 0.05~0.09, Si 0.05~0.30, Mn 1.5~2.0, P≤0.025, S≤0.005, Nb 0~0.07, Ti 0.08~ 0.15, Mo 0.10~0.30, Als 0.015~0.06, Ca 0.0010~0.0030, N≤0.006, surplus is Fe, steel plate THICKNESS CONTROL is at 3.0mm~8.5mm;
(1) continuous casting steel billet uses hot-loading and hot-conveying technique, and charging temperature when slab enters heating furnace is more than 300 DEG C, heating of plate blank Temperature is more than 1200 DEG C;
(2) hot rolling finishing temperature controls at 820~880 DEG C;
(3) use the cooling rate cooling rate more than 25 DEG C/s that strip steel is cooled down after rolling;
(4) oiler temperature control is at 560~640 DEG C;
(5) steel plate through open gentle crosscutting after, heat-treatment lines carry out 550~650 DEG C/10~50min tempering.
CN201410593263.8A 2014-10-30 2014-10-30 A kind of steel for engineering machinery plate and production method thereof Active CN104264052B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201410593263.8A CN104264052B (en) 2014-10-30 2014-10-30 A kind of steel for engineering machinery plate and production method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201410593263.8A CN104264052B (en) 2014-10-30 2014-10-30 A kind of steel for engineering machinery plate and production method thereof

Publications (2)

Publication Number Publication Date
CN104264052A CN104264052A (en) 2015-01-07
CN104264052B true CN104264052B (en) 2016-08-31

Family

ID=52155624

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201410593263.8A Active CN104264052B (en) 2014-10-30 2014-10-30 A kind of steel for engineering machinery plate and production method thereof

Country Status (1)

Country Link
CN (1) CN104264052B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105838973A (en) * 2016-03-28 2016-08-10 黄惠玲 High-strength steel plate and preparation process thereof
CN106929759B (en) * 2017-03-17 2019-04-23 唐山钢铁集团有限责任公司 A kind of 800MPa grades of thin gauge hot rolled strip and its production method
CN107513662A (en) * 2017-09-08 2017-12-26 河钢股份有限公司邯郸分公司 Save the production method of cold forming high intensity steel S700MC low strengths
CN108486464A (en) * 2018-03-30 2018-09-04 湖南华菱涟源钢铁有限公司 900MPa grades of ferrite base tempering steel plates of yield strength and production method
CN111440991B (en) * 2020-04-07 2021-10-08 湖南华菱涟源钢铁有限公司 Hot rolled steel plate with yield strength of 800MPa and manufacturing method thereof

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5037415B2 (en) * 2007-06-12 2012-09-26 新日本製鐵株式会社 High Young's modulus steel plate excellent in hole expansibility and method for producing the same
JP5088021B2 (en) * 2007-07-05 2012-12-05 新日本製鐵株式会社 High-rigidity, high-strength cold-rolled steel sheet and manufacturing method thereof
JP5381900B2 (en) * 2010-05-27 2014-01-08 新日鐵住金株式会社 ERW steel pipe for brace having excellent buckling resistance and manufacturing method thereof

Also Published As

Publication number Publication date
CN104264052A (en) 2015-01-07

Similar Documents

Publication Publication Date Title
CN104264052B (en) A kind of steel for engineering machinery plate and production method thereof
CN104532126B (en) A kind of super high strength hot rolled Q&P steel of low yield strength ratio and its manufacture method
US20160017449A1 (en) 700MPA-Level High-Strength Hot Rolling Q&P Steel And Method Of Manufacturing The Same
JP2018505303A (en) Yield strength 900-1000MPa tempered high strength steel and method for producing the same
WO2018036348A1 (en) Thin thermoformed steel directly rolled using thin slabs and having tensile strength of ≥1500 mpa, and method for producing same
WO2016045266A1 (en) High-toughness hot-rolling high-strength steel with yield strength of 800 mpa, and preparation method thereof
CN104694822A (en) High-strength hot rolled steel plate with 700 MPa grade yield strength and manufacturing method thereof
CN106191678B (en) With the tensile strength >=1700MPa hot formings steel and production method of medium thin slab Direct Rolling
CN110106322B (en) High-strength steel for thin engineering machinery and plate shape control method
CN108754319B (en) Hot forming steel with tensile strength of more than or equal to 1800MPa produced by ESP production line and method
CN107868906A (en) A kind of thin-wall high intensity square and rectangular pipe hot-strip and its manufacture method
CN107868911A (en) A kind of yield strength 600MPa level hot rolled steel plates and its manufacture method
CN105695870A (en) thick hot rolled sheet steel with 450MPa grade yield strength and manufacturing method thereof
CN104846293A (en) High-strength high-toughness steel plate and preparation method thereof
CN102925794B (en) Cold-rolled steel strip for double-layer welded tube and its manufacture mathod
CN108486464A (en) 900MPa grades of ferrite base tempering steel plates of yield strength and production method
CN101906519A (en) Manufacture method of low yield ratio surface layer ultra fine grain low-carbon steel thick plate
CN107574370A (en) 2~10mmNM400 of thickness abrasion-resistant stees and production method
CN104328350A (en) Hardened and tempered steel with yield strength of 960MPa level and manufacturing method of hardened and tempered steel
CN105039848A (en) Production method of 500-600MPa cold-rolled annealed low-alloy and high-strength steel
CN106435380A (en) Microalloyed high-aluminum high-ductility steel plate and manufacturing method thereof
CN105543666B (en) A kind of yield strength 960MPa beam steels and its production method
CN105950972A (en) Thick-specification X80 pipeline steel plate with process time being shortened and manufacturing method thereof
CN106435406B (en) A kind of Millettia pachycarpa weather-resistant steel plate and its manufacturing method
CN107723604A (en) A kind of economical 690MPa levels dual phase steel and preparation method thereof

Legal Events

Date Code Title Description
PB01 Publication
C06 Publication
SE01 Entry into force of request for substantive examination
C10 Entry into substantive examination
GR01 Patent grant
C14 Grant of patent or utility model