Claims
- 1. A process for preparing a steel wire or rod having a tensile strength of greater than 140 kg/mm.sup.2 and a total elongation of about 10.6% or greater, said method consisting of:
- (a) hot rolling a steel consisting essentially of 0.2-0.4%, by weight, of C, and 0.5-2.5%, by weight, of Mn, with the balance iron and inevitable impurities, while controlling the rolling conditions so that intermediate and final rolling temperatures are below 1000.degree. C., and the total reduction ratio at temperatures below 930.degree. C. is greater than 30%; thereby producing a steel consisting of hardened austenite having fine and uniform grains, and
- (b) continuously cooling said steel immediately after rolling to room temperature at an average cooling rate of 20.degree.-250.degree. C./sec., thereby forming a final phase in said steel of high ductility consisting essentially of martensite and a small amount of retained austenite.
- 2. The process of claim 1 wherein said steel further contains at least one element selected from the group consisting of Nb, V, Ti and Zr, in amounts from an amount effective to improve the ductility of said martensitic steel rod up to less than 0.1%, by weight, of Nb, less than 0.1%, by weight, of V, less than 0.3%, by weight, of Ti and less than 0.3%, by weight, of Zr.
Priority Claims (1)
Number |
Date |
Country |
Kind |
56-11031 |
Jan 1981 |
JPX |
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Parent Case Info
This application is a continuation-in-part of pending application Ser. No. 343,220 filed Aug. 4, 1983, now abandoned.
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
343220 |
Aug 1983 |
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