Patent ID: 8052812

Claim:
A method for manufacturing a high carbon cold-rolled steel sheet, comprising the steps of: hot-rolling a steel containing 0.2 to 0.7% C by mass at a finishing temperature of (A r3 transformation point −20° C.) or above to prepare a hot-rolled sheet; cooling the hot-rolled sheet to a temperature of 650° C. or below at a cooling rate ranging from 60° C./s to 115° C./s; coiling the hot-rolled sheet after cooling at a coiling temperature of 600° C. or below; cold-rolling the coiled hot-rolled sheet at a rolling reduction of 30% or more to prepare a cold-rolled sheet; and annealing the cold-rolled sheet at an annealing temperature ranging from 600° C. or larger to A c1 transformation point or lower such that the sheet has a homogeneity of hardness represented by a difference between maximum hardness H v max and minimum hardness H v min , ΔH=(H v max −H v min ), in a sheet thickness direction of 10 or less.