摘要:
The present invention provides spring-use heat treated steel which is cold coiled, can achieve both sufficient atmospheric strength and coiling workability, has a tensile strength of 2000 MPa or more, and can improve the performance as a spring by heat treatment after shaping the spring, that is, heat treated steel for high strength spring containing, by mass %, C: 0.45 to 0.9%, Si: 1.0 to 3.0%, Mn: 0.1 to 2.0%, V: over 0.1 to 1.0%, N: limited to 0.007% or less, and a balance of Fe and unavoidable impurities, and satisfying, in terms of the analyzed value of the extracted residue after heat treatment, [amount of V in filtrate filtered by 0.2 μm filter (mass %)]≧[amount of V in steel (mass %)]×0.4.
摘要:
The present invention provides spring use heat treated steel which is cold coiled, can achieve both sufficient atmospheric strength and coilability, has a tensile strength of 2000 MPa or more, and can improve the performance as a spring by heat treatment after spring fabrication, that is, high strength spring-use heat treated steel characterized by containing, by mass %, C: 0.45 to 0.9%, Si: 1.7 to 3.0%, and Mn: 0.1 to 2.0%, restricting N: to 0.007% or less, having a balance of Fe and unavoidable impurities, and satisfying, in terms of the analyzed value of the extracted residue after heat treatment, [amount of Fe in residue on 0.2 μm filter/[steel electrolysis amount]×100≦1.1.
摘要:
The present invention provides spring steel used for spring steel wire achieving both high strength and cold coilability and spring steel wire, that is, spring steel containing, by mass %, C: 0.45 to 0.70%, Si: 1.0 to 3.0%, Mn: 0.05 to 2.0%, P: 0.015% or less, S: 0.015% or less, N: 0.0015 to 0.0200%, and t-O: 0.0002 to 0.01 and further limiting Al≤0.01% and Ti≤0.003%. Further, it is characterized by satisfying the following regarding the cementite-based spherical carbides present at an observed plane, an occupied area ratio of grains with a circle equivalent diameter of 0.2 μm or more of 7% or less, a density of presence of grains with a circle equivalent diameter of 0.2 to 3 μm of 1/μm2 or less, and a density of presence of grains with a circle equivalent diameter 3 μm or more of 0.001/μm2 or less, having an prior austenite grain size number of #10 or higher and a residual austenite of 15 mass % or less, and having an area ratio of poor regions with a small density of presence of cementite-based carbides of a circle equivalent diameter of 2 μm or more of 3% or less.
摘要:
The present invention provides spring use heat treated steel which is cold coiled, can achieve both sufficient atmospheric strength and coilability, has a tensile strength of 2000 MPa or more, and can improve the performance as a spring by heat treatment after spring fabrication, that is, high strength spring-use heat treated steel characterized by containing, by mass %, C: 0.45 to 0.9%, Si: 1.7 to 3.0%, and Mn: 0.1 to 2.0%, restricting N: to 0.007% or less, having a balance of Fe and unavoidable impurities, and satisfying, in terms of the analyzed value of the extracted residue after heat treatment, [amount of Fe in residue on 0.2 μm filter/[steel electrolysis amount]×100≦1.1.
摘要:
The present invention provides a high strength heat treated steel wire for spring having a tensile strength of 2000 MPa or more which is coiled in the cold state and can achieve both sufficient atmospheric strength and coilability and spring steel used for that steel wire, that is, a high strength heat treated steel wire for a spring characterized by comprising, by mass %, C: 0.5 to 0.9%, Si: 1.0 to 3.0%, Mn: 0.1 to 1.5%, Cr: 1.0 to 2.5%, V: over 0.15 to 1.0%, and Al: 0.005% or less, controlling N to 0.007% or less, further containing one or two of Nb: 0.001 to less than 0.01% and Ti: 0.001 to less 0.005%, and having a tensile strength of 2000 MPa or more, having cementite-based spheroidal carbides and alloy-based spheroidal carbides in a microscopic visual field satisfying an area percentage of carbides with a circle equivalent diameter of 0.2 μm or more of 7% or less and a density of carbides with a circle equivalent diameter of 1 grain/μm2 or less, having a prior austenite grain size number of #10 or more, and having retained austenite of 15 mass % or less.
摘要翻译:本发明提供一种用于弹簧的高强度热处理钢丝,其拉伸强度为2000MPa以上,其被卷绕在冷态中,并且可以获得足够的大气强度和线性,以及用于该钢丝的弹簧钢,即, 用于弹簧的高强度热处理钢丝,其特征在于以质量%计含有C:0.5〜0.9%,Si:1.0〜3.0%,Mn:0.1〜1.5%,Cr:1.0〜2.5%,V:0.15以上 至1.0%,Al:0.005%以下,控制为N = 0.007%以下,进一步含有Nb:0.001〜0.01%以下,Ti:0.001〜0.005%以下,拉伸强度为2000 MPa以上,在微观视场中具有渗碳体系球状碳化物和合金系球状碳化物,其满足圆当量直径为0.2μm以上的碳化物的面积百分比为7%以下,碳化物的密度为圆 当量直径为1粒/ m 2或更小,具有先前的奥氏体晶粒s #10以上,残留奥氏体为15质量%以下。
摘要:
The present invention provides spring steel used for spring steel wire achieving both high strength and cold coilability and spring steel wire, that is, spring steel containing, by mass %, C: 0.45 to 0.70%, Si: 1.0 to 3.0%, Mn: 0.05 to 2.0%, P: 0.015% or less, S: 0.015% or less, N: 0.0015 to 0.0200%, and t-O: 0.0002 to 0.01 and further limiting Al≦0.01% and Ti≦0.003%. Further, it is characterized by satisfying the following regarding the cementite-based spherical carbides present at an observed plane, an occupied area ratio of grains with a circle equivalent diameter of 0.2 μm or more of 7% or less, a density of presence of grains with a circle equivalent diameter of 0.2 to 3 μm of 1/μm2 or less, and a density of presence of grains with a circle equivalent diameter 3 μm or more of 0.001/μm2 or less, having an prior austenite grain size number of #10 or higher and a residual austenite of 15 mass % or less, and having an area ratio of poor regions with a small density of presence of cementite-based carbides of a circle equivalent diameter of 2 μm or more of 3% or less.
摘要:
The present invention provides steel superior in machinability comprised of, by wt %, C: 0.005 to 0.2%, Si: 0.001 to 0.5%, Mn: 0.2 to 3.0%, P: 0.001 to 0.2%, S: 0.03 to 1.0%, T.N: 0.002 to 0.02%, T.O: 0.0005 to 0.035%, and the balance of Fe and unavoidable impurities, said steel satisfying one or both of Mn/S in the steel being 1.2 to 2.8 or an area ratio of pearlite over a grain size of 1 μm in a microstructure of the steel being not more than 5%.
摘要:
The present invention provides a spring steel having both a high strength and a good coiling property after heat treatment, characterized by: containing, in mass, C: 0.4 to 1.2%, Si: 0.9 to 3.0%, Mn: 0.1 to 2.0%, P: 0.015% or less, S: 0.015% or less, Cr: 2.5% or less, and N: 0.001 to 0.015%, with the balance consisting of Fe and unavoidable impurities; and, in the microstructure of the steel after hot rolling, the density of globular cementite carbides 0.2 to 3 μm in circle-equivalent diameter being 0.5 piece/μm2 or less and the density of globular cementite carbides over 3 μm in circle-equivalent diameter being 0.005 piece/μm2 or less.
摘要:
This invention provides an oil-tempered wire having high strength (tensile strength of not less than 1960 MPa) and excellent workability and specifically provides a steel wire for high-strength springs comprising as steel components, in weight percent, C 0.4-0.7% Si 1.2-2.5% Mn 0.1-0.5% Cr 0.4-2.0% Al 0.0001-0.005%, and being limited to P not more than 0.015% and S not more than 0.015%, the balance being Fe and unavoidable impurities, the steel wire having no nonmetallic inclusions of a size greater than 15 &mgr;m, a tensile strength of not less than 1960 MPa, and a yield ratio (&sgr;0.2/&sgr;B) of not less than 0.8 and not greater than 0.9 or a yield ratio (&sgr;0.2/&sgr;B) of not less than 0.8 and an amount of residual austenite of not greater than 6%. This invention also provides a method of producing the steel wire.
摘要:
The present invention provides steel superior in machinability comprised of, by wt %, C: 0.005 to 0.2%, Si: 0.001 to 0.5%, Mn: 0.2 to 3.0%, P: 0.001 to 0.2%, S: 0.03 to 1.0%, T.N: 0.002 to 0.02%, T.O: 0.0005 to 0.035%, and the balance of Fe and unavoidable impurities, said steel satisfying one or both of Mn/S in the steel being 1.2 to 2.8 or an area ratio of pearlite over a grain size of 1 μm in a microstructure of the steel being not more than 5%.