(EN) Provided is a high-carbon cold-rolled steel sheet having a thickness of less than 1.0 mm and capable of having good impact and hardness characteristics after a short solution treatment, and thereafter quenching and low-temperature tempering. A high-carbon cold-rolled steel sheet having a steel sheet chemical composition containing, in terms of mass%, C: 0.85-1.10%, Mn: 0.50-1.0%, Si: 0.10-0.35%, P: 0.030% or less, S: 0.030% or less, and Cr: 0.35-0.45%, and furthermore containing Nb: 0.005-0.020 mass% with the remainder being Fe and unavoidable impurities, having a steel sheet structure in which the average particle diameter (dav) of carbide dispersed in the steel sheet is 0.2-0.7 ([mu]m) and the spheroidization ratio is 90% or higher, and having a thickness of less than 1.0 mm. Mechanical characteristics having an excellent impact characteristic in which the impact value is 5 j/cm<2> or higher and a sufficient hardness characteristic within the range of 600-750 HV can thereby be manifested by a short solution treatment of 3-15 minutes, and thereafter quenching and low-temperature tempering. (ZH) 本发明提供一种高碳冷轧钢板,前述高碳冷轧钢板在实施短时固溶处理和其后的淬火及低温回火处理后,能够具有良好的冲击特性及硬度特性,板厚不足1.0mm。前述高碳冷轧钢板构成为具有:不足1.0mm的厚度,钢板化学成分以质量%计含有:C:0.85~1.10%,Mn:0.50~1.0%,Si:0.10~0.35%,P:0.030%以下,S:0.030%以下,Cr:0.35~0.45%,进而,含有Nb:0.005~0.020质量%,剩余部分为Fe及不可避杂质;而且碳化物分散于钢板中的钢微观结构具有0.2~0.7(μm)的平均粒径(dav)和90%以上的球化率。
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