摘要 |
A method for manufacturing a steel member which comprises the steps of preparing a steel material of a composition containing C in a quantity of 0.15 to 0.35 wt %, Si in a quantity of not greater than 0.50 wt %, Mo in a quantity of 0.05 to 0.50 wt %, Mn in a quantity of 0.50 to 1.30 wt %, Cr in a quantity of 0.50 to 1.30 wt %, V in a quantity of 0.05 to 0.20 wt %, N in a quantity not greater than 0.02 wt %, Al in a quantity of not greater than 0.10 wt % and Fe being the balance relative to the total weight of the steel material, wherein the product of the sum of the Mn content and the Cr content times the Mo content is chosen to be within the range of 0.1 to 0.6, hot-forging the steel material at a predetermined heating temperature to provide the steel member, and continuously cooling the steel member at a predetermined cooling speed of 0.4 DEG to 4.0 DEG C./sec to impart a substantially bainite structure or a combined bainite and ferrite structure to the steel member.
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