| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily provide the annular member having a desired surface hardness and roundness at a low cost. SOLUTION: A steel, which contains at least 0.4-1.5 wt.% Si, is subjected to tempering/straightening at a straightening rate of >=0.2% and a tempering parameter in a range of 8570-9250. The annular member tempered/straightened in this method has a hardness Hv of >=700 and a deformation straightening rate of >=70% further has excellent roundness while maintaining surface hardness.</p> |
