| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To impart an extremely long fatigue life, e.g. an L<SB>10</SB>life of≥100×10<SP>6</SP>cycles, to a steel material used in a machine part such as a bearing. <P>SOLUTION: The steel comprises, by mass%, 0.95-1.10% C, 0.15-0.35% Si, 0.30-0.50% Mn and 1.30-1.60% Cr. The steel contains inclusions having major axes of≥30μm in the number of≤35 pieces/kg with roundness of≥1.0 but <1.4 and≤90 pieces/kg with roundness of≥1.4. The steel material is produced using a vacuum high-frequency induction furnace (VIF), an LF device or an RH device. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
