摘要:
Hot-rolled steel having a tensile strength of at least 950MPa and a microstructure comprising bainite at an area ratio of 70% or more; the balance being: martensite at an area ratio of 30%or less, and optionally ferrite at an area ratio of 20% or less. The hot- rolled steel has a chemical containing (in mass-%):C: 0.07-0.10, Si: 0.01-0.25, Mn: 1.5- 2.0, Cr: 0.5-1.0, Ni: 0.1-0.5, Cu: 0.1-0.3, Mo: 0.01 -0.2, Al: 0.01 -0.05, Nb: 0.015-0.04, V: 0-0.1, i.e. optionally up to 0.1 mass-% Vanadium, Ti: 0-0.1, whereby the balance is Fe and unavoidable impurities.
摘要:
A method for producing a zinc or zinc-alloy coated steel sheet with a tensile strength higher than 900 MPa, for the fabrication of resistance spot welds containing in average not more than two Liquid Metal Embrittlement cracks per weld having a depth of 100μιη or more, comprising the successive steps of providing a cold-rolled steel sheet, the nominal composition of which contains, in weight percent: 0.07% ≤ C ≤ 0.5%, 0.3% ≤ Mn ≤ 5%, 0.010% ≤ Al ≤1 %, 0.010% ≤ Si ≤ 2.45%, with 0.35% ≤ (Si+AI) ≤ 2.5%,, 0.001 % ≤ Cr ≤ 1.0%, 0.001 % ≤ Mo ≤ 0.5%, and optionally, 0.005% ≤ Nb ≤0.1 %, 0.005% ≤ V ≤ 0.2%, 0.005% ≤ Ti ≤ 0.1 %, 0.0001 % ≤ B ≤ 0.004%, 0.001 % ≤ Cu ≤ 0.5%, 0.001 % ≤ Ni ≤ 1.0%, the remainder being iron and unavoidable impurities from the smelting, heating said cold-rolled steel sheet up to a temperature T1 comprised between 550°C and Ac1 +50°C in a furnace zone with an atmosphere (A1) containing from 2 to 15% hydrogen by volume, the balance being nitrogen and unavoidable impurities, so that the iron is not oxidized, then adding in the furnace atmosphere at least one element selected from liquid water, water steam or oxygen at a temperature T≥T1, so to obtain an atmosphere (A2) with a dew point comprised between 15°C and the temperature Te of the iron/iron oxide equilibrium dew point, then heating the sheet from said temperature T 1 up to a temperature T 2 comprised between 720°C and 1000°C in a furnace zone under an atmosphere (A2) of nitrogen containing from 2 to 15% hydrogen and more than 0.1 % CO by volume, then soaking the sheet at T 2 , then cooling the sheet, then coating the sheet with zinc or zinc-alloy coating.
摘要:
Austempered steel for components requiring high strength and high ductility and/or fracture toughness, which has a silicon content of 3.1 weight-% to 4.4 weight-% and a carbon content of 0.4 weight-% to 0.6 weight-%. The microstructure of the austempered steel is ausferritic or superbainitic.
摘要:
L'invention concerne une tôle d'acier à « effet TRIP » laminée à froid et recuite présentant une formabilité et une soudabilité améliorée, de résistance comprise entre 780 et 900MPa et d'allongement à rupture supérieur à 19 %, dont la composition comprend, les teneurs étant exprimées en poids : 0,17% ≤ C ≤ 0,25%, 1,5% ≤ Mn ≤ 2%, 0,50% ≤ Si ≤ 1%, 0,50% ≤ Al ≤ 1,2%, étant entendu que Si +AI ≥ 1,30%, le reste de la composition étant constitué de fer et d'impuretés inévitables résultant de l'élaboration, la microstructure de la tôle est constituée de 65 à 85 % de ferrite, de 15 à 35 % d'îlots de martensite et d'austénite résiduelle, la taille moyenne desdits îlots de martensite et d'austénite résiduelle est inférieure à 1,3 micromètre, leur facteur de forme moyen étant inférieur à 3.
摘要翻译:本发明涉及冷轧和退火的TRIP钢板,其可成型并且具有改善的可焊性,其强度在780至900MPa之间,断裂伸长率大于19% 其组成包括以重量百分比表示的含量:0.17%= C = 0.25%,1.5%= Mn = 2%,0.5%= Si = 1%,0.5%= Al = 1.2% Si + Al = 1.30%,剩余的由铁和不可避免的杂质组成的组成由生产产生,钢板的组织为65-85%的铁,15-35%的残余马氏体和奥氏体的岛 所述残余马氏体和奥氏体岛的平均尺寸小于1.3微米,其平均形状因子小于3
摘要:
Ce fil de forme, de qualité NACE, en acier au carbone faiblement allié destiné à être utilisé dans le secteur de l'exploitation pétrolière off shore, se caractérise en ce qu'il présente la composition chimique suivante, exprimée en pourcentages pondéraux de la masse totale, le reste étant du fer et les impuretés inévitables venant de l'élaboration du métal à l'état liquide: 0,75
摘要翻译:NACE级的这种异型钢丝是用于海上石油开采领域的低合金碳钢,其特征在于具有如下化学成分,以总质量的百分比表示:0.75 <% C <0.95; 0.30 <%Mn <0.85; Cr = 0.4%; V = 0.16%; Si = 1.40%,优选= 0.15%; 并且任选地不超过0.06%的Al,不超过0.1%的Ni和不超过0.1%的Cu,余量为铁和由液态熔融金属产生的不可避免的杂质,并且从钢 将热轧棒材冷却至室温,然后直径约5〜30mm,首先将该起始棒进行热机械处理,包括依次进行的两个连续步骤,即等温骤冷,使其成为 均匀的珍珠岩微观结构,然后以整体加工硬化程度(或减少率)至多为50%至80%之间进行冷的机械转化操作,以使线材具有确定的形状,并且其形状 然后将由此获得的线材进行短时间内进行的低于Ac1(优选410至710℃)的恢复热处理,从而获得所需的最终机械性能。
摘要:
A method for manufacturing mechanical components made of spheroidal cast iron, comprising the following steps: - providing a casting of a mechanical component made of cast iron having a structure which is at least partially ferritic and has a carbon content ranging from 2.5% to 4.0% and a silicon content ranging from 2.0% to 3.5%; - bringing the cast iron casting having an at least partially ferritic structure to a temperature for partial austenitizing which is higher than the lower limit austenitizing temperature (Ac1) and lower than the upper limit austenitizing temperature (Ac3) for a time required to obtain an at least partially austenitic structure; - performing a thermal treatment for isothermal hardening at a temperature ranging from 250°C to 400°C in order to obtain a matrix which has at least partially a pearlitic-ferritic or perferritic structure.
摘要:
A method for manufacturing mechanical components made of spheroidal cast iron, comprising the following steps: - providing a casting of a mechanical component made of cast iron having a structure which is at least partially ferritic and has a carbon content ranging from 2.5% to 4.0% and a silicon content ranging from 2.0% to 3.5%; - bringing the cast iron casting having an at least partially ferritic structure to a temperature for partial austenitizing which is higher than the lower limit austenitizing temperature (AcI) and lower than the upper limit austenitizing temperature (Ac3) for a time required to obtain an at least partially austenitic structure; - performing a thermal treatment for isothermal hardening at a temperature ranging from 250°C to 400°C in order to obtain a matrix which has at least partially a pearlitic-ferritic or perferritic structure.