摘要:
A cold-rolled and heat treated steel sheet, having a composition comprising 0.1% ≤ C≤0.4%, 3.5%≤Mn≤8.0%, 0.1%≤Si≤1.5%, Al≤ 3%, Mo≤0.5%, Cr≤1%, Nb≤0.1%, Ti≤0.1%, V≤0.2%, B≤0.004%, 0.002%≤N≤0.013%, S≤0.003%, P≤0.015%. The structure consists of, in surface fraction: between 8 and 50% of retained austenite, at most 80% of intercritical ferrite, the ferrite grains, if any, having an average size of at most 1.5 μm, and at most 1% of cementite, the cementite particles having an average size lower than 50 nm, martensite and/or bainite.
摘要:
The invention deals with a cold rolled and heat treated steel sheet, the steel comprising, in weight percentage, 0.18% ≤ carbon ≤ 0.24%, 1.5% ≤ manganese ≤ 2.5%, 1.2% ≤ silicon ≤ 2%, 0.01% ≤ aluminum ≤0.06%, 0.2%≤ chromium ≤ 0.5%, phosphorus ≤ 0.02%, sulfur ≤ 0.03%, and optionally one or more of the following elements niobium ≤ 0.06%, titanium ≤ 0.08%, vanadium ≤0.1%, calcium ≤ 0.005% and the balance including iron and unavoidable impurities, the steel sheet having a microstructure comprising 0% to 15% of tempered martensite, 10% to 15% of residual austenite and optionally up to 30% of ferrite in area fractions, the balance being made of bainite, bainite content being at least 55% and having an internal oxide layer of 3 microns or less on both surfaces of said steel sheet. It also deals with a manufacturing method and with use of such grade for making vehicle parts.
摘要:
Steel section having a thickness of at least 100mm and method of manufacturing the same The invention deals with a H-beam steel section, comprising a web central portion connected on each side to a flange portion having a thickness of at least 100mm, such steel section having a composition comprising, in weight percentage: C : 0.06 - 0.16 % Mn : 1.10 - 2.00 % Si : 0.10-0.40% Cu : 0.001 - 0. 50 % Ni : 0.001 - 0.30 % Cr: 0.001 - 0. 50 % Mo : 0.001 - 0.20 % V: 0.06 - 0.12 % N : 0.0050% - 0.0200 % Al ≤ 0.040 % P ≤ 0.040 % S ≤ 0.030 % and comprising optionally one or more of the following elements, in weight percentage: Ti
摘要:
Acier inoxydable martensitique, caractérisé en ce que sa composition est, en pourcentages pondéraux : 0,005% ≤ C ≤ 0,30%; 0,20% ≤ Mn ≤ 2,0%; traces % ≤ Si ≤,0%; 0,20% ≤ Mn + Si ≤ 1,5%; traces ≤ S ≤ 0,01%; 0 ≤ 10 000 x Mn x S ≤ 40; traces ≤ P ≤ 0,04%; 10,5% ≤ Cr ≤ 17,0%, avec [Cr - 10.3 - 80 x (C + N) 2 ] ≤ (Mn + Ni); traces ≤ Ni ≤ 4,0%; traces ≤ Mo ≤ 2,0%; traces ≤ Mo + 2W ≤ 2,0%; traces ≤ Cu ≤ 2,0%; traces ≤ Ti ≤ 0,5%; traces ≤ V ≤ 0,3%; traces ≤ Zr ≤ 0,5%; traces ≤ Al ≤ 0,2%; traces ≤ O ≤ 400 ppm; traces ≤ Ta ≤ 0,3%; traces ≤ Nb ≤ 0,3%; 0,25 ≤ (Nb + Ta)/(C + N) ≤ 8; Nb ≥ [1,2 (C + N) - 0,1]%; 0,009% ≤ N ≤ 0,2%; traces ≤ Co ≤ 2,0%; traces ≤ Cu + Co ≤ 2,0%;traces ≤ Cu + Co + Ni ≤ 4,0%; traces ≤ B ≤ 0,1%; traces ≤ terres rares + Y ≤ 0,06%; traces ≤ Ca ≤ 20ppm; le reste étant du fer et des impuretés résultant de l'élaboration; et en ce que sa microstructure comporte au moins 75% de martensite, au plus 20% de ferrite et au plus 0,5% de carbures, la taille des grains de ferrite étant comprise entre 4 et 80 μm, de préférence entre 5 et 40 μm. Procédé de fabrication de cet acier.
摘要:
본 발명의 일 측면은 중량%로, C: 0.02~0.05%, Si: 0.01~0.3%, Mn: 1.0~1.6%, Ti: 0.04~0.1%, Nb: 0.01~0.05%, N: 0.008% 이하, 나머지 Fe 및 기타 불가피한 불순물을 포함하며, 하기 식(1)을 만족하고, 미세조직은 95면적% 이상의 페라이트 및 (Ti, Nb)C 복합석출물을 포함하고, 직경 10nm 이하의 (Ti, Nb)C 복합석출물 개수가 직경 10nm 초과의 (Ti, Nb)C 복합석출물 개수의 5배 이상으로 형성되어 있는 재질 균일성 및 구멍확장성이 우수한 석출강화형 열연강판에 관한 것이다. 식(1): 0.35 ≤ (Ti+Nb+V+Mo)/(C+N) ≤ 0.70 (단, 상기 식(1)에서 각 원소기호는 각 원소의 at. %를 의미하며, 강 중에 포함되지 않은 원소는 0으로 계산한다.)
摘要翻译:
以重量%计,本发明的一个方面,含有C:0.02〜0.05%以下,Si:0.01〜0.3%以下,Mn:1.0〜1.6%以下,Ti:0.04〜0.1%以下,Nb:0.01〜 0.05%,N:满足0.008%或以下,Fe和其它不可避免的包括杂质,平衡和下式(1),微结构包含至少95体积%的铁素体面积和的(Ti,Nb)的C复合析出物,并且直径 10nm以下的(Ti,Nb)的C复合析出物的复合析出物材料的均匀性和高的析出硬化型热轧钢板的孔放大能力的数目形成直径10nm的比(钛,铌)C更大的数作为至少5倍 会的。 (1):0.35≤(Ti + Nb + V + Mo)/(C + N)≤0.70其中各符号代表各元素的原子百分比, 元素被计为零。) P>
摘要:
This disclosure describes new high temperature, radiation-resistant, ferritic-martensitic steel compositions. The new steels generally contain 9.0-12.0 wt. % Cr, 0.001-1.0 wt. % Mn, 0.001-2.0 wt. % Mo, 0.001-2.5 wt. % W, and 0.1-0.3 wt. % C, with the balance being primarily Fe. More specifically, steels having from 10.0-12.0 wt. % Cr are considered particularly advantageous. Small amounts of N, Nb, V, Ta, Ti, Zr, and B may or may not also be present, depending on the particular embodiment. Impurities may be present in any embodiment, in particular impurities of less than 0.01 wt. % S, less than 0.04 wt. % P, less than 0.04 wt. % Cu, less than 0.05 wt. % Co, and less than 0.03 wt. % As are contemplated. Examples of these steels exhibit improved fracture toughness and reduced thermal creep and swelling.
摘要:
A method for producing a steel sheet, the method comprising the following successive steps: providing a cold-rolled steel sheet, the chemical composition of the steel containing in weight %: 0.15% ≤ C ≤ 0.23%, 2.0 % ≤ Mn ≤ 2.8%, 1.0% ≤ Si ≤ 2.1%, 0.02% ≤ Al ≤1.0%, with 1.7% ≤ Si+Al ≤ 2.1%, 0 ≤ Nb ≤ 0.035 %, 0 ≤ Mo ≤ 0.3 %, 0 ≤ Cr ≤ 0.4 %, the remainder being Fe and unavoidable impurities, annealing the steel sheet at an annealing temperature T A so as to obtain a structure comprising at least 65% of austenite and up to 35% of intercritical ferrite, quenching the sheet at a cooling rate of at least 20°C/s from a temperature of at least 600°C down to a quenching temperature QT comprised between Ms-170°C and Ms- 80°C, heating the sheet up to a partitioning temperature PT between 350°C and 450°C and maintaining the sheet at this temperature for a partitioning time Pt comprised between 80s and 440s, immediately cooling the sheet down to the room temperature, the steel sheet having a final microstructure consisting of, in surface fraction: - between 40% and 70% of tempered martensite, - between 7% and 15% of retained austenite, - between 15% and 35% of ferrite, - at most 5% of fresh martensite, - at most 15% of bainite.