COLD-ROLLED STEEL SHEET
    1.
    发明申请
    COLD-ROLLED STEEL SHEET 有权
    冷轧钢板

    公开(公告)号:US20120009434A1

    公开(公告)日:2012-01-12

    申请号:US13257639

    申请日:2009-10-01

    IPC分类号: B21C1/00

    摘要: Disclosed is a high-strength cold-rolled steel sheet which has improved stretch-flange formability while keeping excellent hydrogen embrittlement resistance. The cold-rolled steel sheet comprises 0.03 to 0.30% by mass of C, 3.0% by mass or less (including 0% by mass) of Si, more than 0.1% by mass and not more than 2.8% by mass of Mn, 0.1% by mass or less of P, 0.005% by mass or less of S, 0.01% by mass or less of N, and 0.01 to 0.50% by mass of Al. The cold-rolled steel sheet additionally comprises V in an amount of 0.001 to 1.00% by mass or one or more elements selected from Nb, Ti and Zr in the total amount of 0.01% by mass or more, with the remainder being made up by iron and unavoidable impurities, wherein the contents of one or more elements selected from Nb, Ti and Zr fulfils the requirement represented by the following formula: [% C]−[% Nb]/92.9×12−[% Ti]/47.9×12−[% Zr]/91.2×12>0.03. In the cold-rolled steel sheet, the area ratio of tempered martensite is 50% or more (including 100%), and ferrite makes up the remainder. In the cold-rolled steel sheet, the distribution of precipitates in the tempered martensite is as follows: the number of precipitates each having a circle-equivalent diameter of 1 to 10 nm is 20 particles or more per 1 μm2 of the tempered martensite and the number of precipitates each containing V or at least one element selected from Nb, Ti and Zr and each having a circle-equivalent diameter of 20 nm or more is 10 particles or less per 1 μm2 of the tempered martensite.

    摘要翻译: 公开了一种在保持优异的耐氢脆性的同时具有改进的拉伸凸缘成形性的高强度冷轧钢板。 该冷轧钢板包含C:0.03〜0.30质量%,Si:3.0质量%以下(含有0质量%)的Si,0.1质量%以上且2.8质量%以下的Mn,0.1 以质量%以下的P,0.005质量%以下的S,0.01质量%以下的N和0.01〜0.50质量%的Al。 冷轧钢板另外包含0.001〜1.00质量%的V或者选自Nb,Ti和Zr中的一种以上的元素,总量为0.01质量%以上,余量由 铁和不可避免的杂质,其中选自Nb,Ti和Zr中的一种或多种元素的含量满足下式所示的要求:[%C] - [%Nb] /92.9×12- [%Ti] /47.9× 12- [%Zr] /91.2×12> 0.03。 在冷轧钢板中,回火马氏体的面积比为50%以上(包括100%),铁素体构成剩余部分。 在冷轧钢板中,回火马氏体中析出物的分布如下:圆形当量直径为1〜10nm的析出物的个数为每1μm2回火马氏体为20个以上, 每个含有V的析出物数量或选自Nb,Ti和Zr中的至少一种元素,每个圆当量直径为20nm以上的析出物的数量为每1μm2的回火马氏体为10个以下。

    Cold-rolled steel sheet
    2.
    发明授权
    Cold-rolled steel sheet 有权
    冷轧钢板

    公开(公告)号:US08876986B2

    公开(公告)日:2014-11-04

    申请号:US13257639

    申请日:2009-10-01

    摘要: Disclosed is a high-strength cold-rolled steel sheet having improved stretch-flange formability and excellent hydrogen embrittlement resistance. In addition to Fe, C, Si, Mn, P, S, N, and Al, the steel sheet contains V or at least one element of Nb, Ti and Zr. The contents of the at least one element of Nb, Ti and Zr, if present, satisfy the expression of [% C]−[% Nb]/92.9×12−[% Ti]/47.9×12−[% Zr]/91.2×12>0.03. The steel sheet has an area ratio of tempered martensite of 50% or more with ferrite as the remainder. The number of precipitates having a circle-equivalent diameter of 1 to 10 nm is 20 particles or more per 1 μm2 of the tempered martensite. The number of precipitates containing V or the at least one element of Nb, Ti and Zr and having a circle-equivalent diameter of 20 nm or more is 10 particles or less per 1 μm2 of the tempered martensite.

    摘要翻译: 公开了一种具有改善的拉伸凸缘成形性和优异的耐氢脆性的高强度冷轧钢板。 除了Fe,C,Si,Mn,P,S,N和Al之外,钢板含有V或Nb,Ti和Zr中的至少一种元素。 如果存在Nb,Ti和Zr的至少一种元素的含量满足[%C] - [%Nb] /92.9×12 - [%Ti] / 47.9×12 - [%Zr] / 91.2×12> 0.03。 钢板的回火马氏体的面积比为50%以上,其余为铁素体。 圆当量直径为1〜10nm的析出物的数量为每1μm2的回火马氏体为20个以上。 包含V或Nb,Ti和Zr的至少一种元素的圆当量直径为20nm以上的析出物的数量为每1μm2的回火马氏体为10个以下。

    HIGH-STRENGTH COLD-ROLLED STEEL SHEET
    3.
    发明申请
    HIGH-STRENGTH COLD-ROLLED STEEL SHEET 有权
    高强度冷轧钢板

    公开(公告)号:US20100252147A1

    公开(公告)日:2010-10-07

    申请号:US12742323

    申请日:2008-11-20

    摘要: The invention provides a high-strength cold-rolled steel sheet which is improved in elongation and stretch-flangeability and exhibits more excellent formability. The high-strength cold-rolled steel sheet has a composition which contains by mass C: 0.03 to 0.30%, Si: 0.1 to 3.0%, Mn: 0.1 to 5.0%, P: 0.1% or below, S: 0.005% or below, N: 0.01% or below, and Al: 0.01 to 1.00% with the balance consisting of iron and unavoidable impurities. The high-strength cold-rolled steel sheet has a structure which comprises at least 40% (up to 100% inclusive) in terms of area fraction of tempered martensite having a hardness of 300 to 380 Hv and the balance ferrite. The cementite particles in the tempered martensite take such dispersion that 10 or more cementite particles having equivalent-circle diameters of 0.02 to less than 0.1 μm are present per one μm2 of the tempered martensite and three or fewer cementite particles having equivalent-circle diameters of 0.1 μm or above are present per one μm2 of the tempered martensite.

    摘要翻译: 本发明提供了一种提高伸长率和拉伸凸缘性的高强度冷轧钢板,并且具有更优异的成形性。 高强度冷轧钢板的组成为C:0.03〜0.30%,Si:0.1〜3.0%,Mn:0.1〜5.0%,P:0.1%以下,S:0.005%以下 ,N:0.01%以下,Al:0.01〜1.00%,余量由铁和不可避免的杂质构成。 高强度冷轧钢板具有以硬度为300〜380Hv的回火马氏体的面积率和平衡铁素体为至少40%(含有100%以上)的结构。 回火马氏体中的渗碳体颗粒采用这样的分散体,每1μm回火马氏体和三个或更少个当量圆直径为0.1的渗碳体颗粒存在10个或更多个当量圆直径为0.02至小于0.1μm的渗碳体颗粒 每1μm2的回火马氏体存在1μm以上。

    COLD-ROLLED STEEL SHEET AND METHOD FOR PRODUCING THE SAME
    4.
    发明申请
    COLD-ROLLED STEEL SHEET AND METHOD FOR PRODUCING THE SAME 有权
    冷轧钢板及其制造方法

    公开(公告)号:US20120012231A1

    公开(公告)日:2012-01-19

    申请号:US13258823

    申请日:2010-04-02

    摘要: A cold-rolled steel sheet of the present invention which has a composition containing, in terms of % by mass, C: 0.05-0.30%, Si: 3.0% or less (including 0%), Mn: 0.1-5.0%, P: 0.1% or less (including 0%), S: 0.010% or less (including 0%), and Al: 0.001-0.10%, and remainder being mainly iron, and which has a structure comprising, in terms of area ratio, 10-80% ferrite, less than 5% (including 0%) of the sum of retained austenite and martensite, and a hard phase as the remainder. The steel sheet gives a KAM value frequency distribution curve in which the relationship between the proportion of frequency having a KAM value ≦0.4, XKAM≦0.4°, and the area ratio of ferrite, Vα satisfies XKAM≦0.4°/Vα≧0.8 and the proportion of frequency having a KAM value in the range of 0.6-0.8, XKAM=0.6-0.8° is 10-20%. In the hard phase adjoining the ferrite, cementite, grains having an equivalent circle diameter of 0.1 μm or larger exist so that three or less such cementite grains are dispersed per μm2 of the hard phase. The steel sheet has improved balance between elongation and stretch flangeability and has better formability.

    摘要翻译: 本发明的冷轧钢板,其组成为以质量%计含有C:0.05〜0.30%,Si:3.0%以下(含0%),Mn:0.1-5.0%,P :0.1%以下(包括0%),S:0.010%以下(包括0%),Al:0.001-0.10%,余量主要为铁,其结构为面积比, 10-80%的铁素体,小于残留奥氏体和马氏体之和的5%(包括0%),剩余部分为硬质相。 钢板给出KAM值频率分布曲线,其中具有KAM值< lE; 0.4,XKAM≦̸ 0.4°的频率的比例与铁素体的面积比Vα之间的关系满足XKAM≦̸ 0.4°/Vα≥0.8,以及 KAM值在0.6-0.8,XKAM = 0.6-0.8°范围内的频率比例为10-20%。 在与铁素体相邻的硬相中,存在具有当量圆直径为0.1μm以上的渗碳体,每μm2硬相分散3个以下的渗碳体粒子。 钢板具有提高伸长率和拉伸凸缘性之间的平衡,并且具有更好的成形性。

    Cold-rolled steel sheet and method for producing the same
    5.
    发明授权
    Cold-rolled steel sheet and method for producing the same 有权
    冷轧钢板及其制造方法

    公开(公告)号:US08840738B2

    公开(公告)日:2014-09-23

    申请号:US13258823

    申请日:2010-04-02

    摘要: A cold-rolled steel sheet of the present invention which has a composition containing, in terms of % by mass, C: 0.05-0.30%, Si: 3.0% or less (including 0%), Mn: 0.1-5.0%, P: 0.1% or less (including 0%), S: 0.010% or less (including 0%), and Al: 0.001-0.10%, and remainder being mainly iron, and which has a structure comprising, in terms of area ratio, 10-80% ferrite, less than 5% (including 0%) of the sum of retained austenite and martensite, and a hard phase as the remainder. The steel sheet gives a KAM value frequency distribution curve in which the relationship between the proportion of frequency having a KAM value ≦0.4, XKAM≦0.4°, and the area ratio of ferrite, Vα satisfies XKAM≦0.4°/Vα≧0.8 and the proportion of frequency having a KAM value in the range of 0.6-0.8, XKAM=0.6-0.8° is 10-20%. In the hard phase adjoining the ferrite, cementite, grains having an equivalent circle diameter of 0.1 μm or larger exist so that three or less such cementite grains are dispersed per μm2 of the hard phase. The steel sheet has improved balance between elongation and stretch flangeability and has better formability.

    摘要翻译: 本发明的冷轧钢板,其组成为以质量%计含有C:0.05〜0.30%,Si:3.0%以下(含0%),Mn:0.1-5.0%,P :0.1%以下(包括0%),S:0.010%以下(包括0%),Al:0.001-0.10%,余量主要为铁,其结构为面积比, 10-80%的铁素体,小于残留奥氏体和马氏体之和的5%(包括0%),剩余部分为硬质相。 钢板给出KAM值频率分布曲线,其中具有KAM值< lE; 0.4,XKAM≦̸ 0.4°的频率的比例与铁素体的面积比Vα之间的关系满足XKAM≦̸ 0.4°/Vα≥0.8,以及 KAM值在0.6-0.8,XKAM = 0.6-0.8°范围内的频率比例为10-20%。 在与铁素体相邻的硬相中,存在具有当量圆直径为0.1μm以上的渗碳体,每μm2硬相分散3个以下的渗碳体粒子。 钢板具有提高伸长率和拉伸凸缘性之间的平衡,并且具有更好的成形性。

    High-strength cold-rolled steel sheet
    6.
    发明授权
    High-strength cold-rolled steel sheet 有权
    高强度冷轧钢板

    公开(公告)号:US08679265B2

    公开(公告)日:2014-03-25

    申请号:US12742323

    申请日:2008-11-20

    IPC分类号: C22C38/00 C22C38/22 C22C38/08

    摘要: The invention provides a high-strength cold-rolled steel sheet which is improved in elongation and stretch-flangeability and exhibits more excellent formability. The high-strength cold-rolled steel sheet has a composition which contains by mass C: 0.03 to 0.30%, Si: 0.1 to 3.0%, Mn: 0.1 to 5.0%, P: 0.1% or below, S: 0.005% or below, N: 0.01% or below, and Al: 0.01 to 1.00% with the balance consisting of iron and unavoidable impurities. The high-strength cold-rolled steel sheet has a structure which comprises at least 40% (up to 100% inclusive) in terms of area fraction of tempered martensite having a hardness of 300 to 380 Hv and the balance ferrite. The cementite particles in the tempered martensite take such dispersion that 10 or more cementite particles having equivalent-circle diameters of 0.02 to less than 0.1 μm are present per one μm2 of the tempered martensite and three or fewer cementite particles having equivalent-circle diameters of 0.1 μm or above are present per one μm2 of the tempered martensite.

    摘要翻译: 本发明提供了一种提高伸长率和拉伸凸缘性的高强度冷轧钢板,并且具有更优异的成形性。 高强度冷轧钢板的组成为C:0.03〜0.30%,Si:0.1〜3.0%,Mn:0.1〜5.0%,P:0.1%以下,S:0.005%以下 ,N:0.01%以下,Al:0.01〜1.00%,余量由铁和不可避免的杂质构成。 高强度冷轧钢板具有以硬度为300〜380Hv的回火马氏体的面积率和平衡铁素体为至少40%(含有100%以上)的结构。 回火马氏体中的渗碳体颗粒采用这样的分散体,每1μm回火马氏体和三个或更少个当量圆直径为0.1的渗碳体颗粒存在10个或更多个当量圆直径为0.02至小于0.1μm的渗碳体颗粒 每1μm2的回火马氏体存在1μm以上。

    Cold rolled steel sheet
    7.
    发明授权
    Cold rolled steel sheet 有权
    冷轧钢板

    公开(公告)号:US08343288B2

    公开(公告)日:2013-01-01

    申请号:US12919159

    申请日:2009-03-06

    IPC分类号: C22C38/44

    摘要: Provided are the following cold-rolled steel sheets: 1) a cold-rolled steel sheet having higher stretch flangeability than conventional steels; 2) a cold-rolled steel sheet having a higher balance between elongation and stretch flangeability than conventional steels; and 3) a cold-rolled steel sheet heightened in all of yield stress, elongation, and stretch flangeability. The cold-rolled steel sheets are characterized by containing 0.03-0.30 mass % carbon, up to 3.0 mass % (including 0 mass %) silicon, 0.1-5.0 mass % manganese, up to 0.1 mass % phosphorus, less than 0.01 mass % sulfur, up to 0.01 mass % nitrogen, and 0.01-1.00 mass % aluminum and having a structure which comprises tempered martensite in an amount of 50% or more (including 100%) in terms of areal proportion and in which the remainder is ferrite. The steel sheets are further characterized in that at least one of the following structural factors has been regulated: the proportions of cementite particles and of the ferrite grains in the tempered martensite and the dislocation density in all structures.

    摘要翻译: 提供以下冷轧钢板:1)具有比常规钢更高的拉伸凸缘性的冷轧钢板; 2)与常规钢相比,延伸率和拉伸凸缘性之间的平衡比较高的冷轧钢板; 和3)在所有屈服应力,伸长率和拉伸凸缘性方面提高的冷轧钢板。 冷轧钢板的特征在于,含有0.03-0.30质量%的碳,至多3.0质量%(包括0质量%)的硅,0.1-5.0质量%的锰,至多0.1质量%的磷,小于0.01质量%的硫 ,至多0.01质量%的氮和0.01〜1.00质量%的铝,并且具有以面积比例计为50%以上(包括100%)量的回火马氏体,其余为铁素体的结构。 钢板的特征还在于,以下结构因素中的至少一个已被调节:回火马氏体中的渗碳体颗粒和铁素体晶粒的比例以及所有结构中的位错密度。

    COLD ROLLED STEEL SHEET
    8.
    发明申请
    COLD ROLLED STEEL SHEET 有权
    冷轧钢板

    公开(公告)号:US20110005643A1

    公开(公告)日:2011-01-13

    申请号:US12919159

    申请日:2009-03-06

    摘要: Provided are the following cold-rolled steel sheets: 1) a cold-rolled steel sheet having higher stretch flangeability than conventional steels; 2) a cold-rolled steel sheet having a higher balance between elongation and stretch flangeability than conventional steels; and 3) a cold-rolled steel sheet heightened in all of yield stress, elongation, and stretch flangeability. The cold-rolled steel sheets are characterized by containing 0.03-0.30 mass % carbon, up to 3.0 mass % (including 0 mass %) silicon, 0.1-5.0 mass % manganese, up to 0.1 mass % phosphorus, less than 0.01 mass % sulfur, up to 0.01 mass % nitrogen, and 0.01-1.00 mass % aluminum and having a structure which comprises tempered martensite in an amount of 50% or more (including 100%) in terms of areal proportion and in which the remainder is ferrite. The steel sheets are further characterized in that at least one of the following structural factors has been regulated: the proportions of cementite particles and of the ferrite grains in the tempered martensite and the dislocation density in all structures.

    摘要翻译: 提供以下冷轧钢板:1)具有比常规钢更高的拉伸凸缘性的冷轧钢板; 2)与常规钢相比,延伸率和拉伸凸缘性之间的平衡比较高的冷轧钢板; 和3)在所有屈服应力,伸长率和拉伸凸缘性方面提高的冷轧钢板。 冷轧钢板的特征在于,含有0.03-0.30质量%的碳,至多3.0质量%(包括0质量%)的硅,0.1-5.0质量%的锰,至多0.1质量%的磷,小于0.01质量%的硫 ,至多0.01质量%的氮和0.01〜1.00质量%的铝,并且具有以面积比例计为50%以上(包括100%)量的回火马氏体,其余为铁素体的结构。 钢板的特征还在于,以下结构因素中的至少一个已被调节:回火马氏体中的渗碳体颗粒和铁素体晶粒的比例以及所有结构中的位错密度。