| 摘要 |
PROBLEM TO BE SOLVED: To provide a carburizing material suitable as the material for a member such as a spider desired to have a fatigue strength including torsional or bending strength and further toughness. SOLUTION: A carburizing treatment is applied to a steel material containing, by mass, 0.1-0.3% C, ≤0.5% Si, ≤1.5% Mn, 0.35-0.8% Cr, 0.15-0.7% Mo, 0.005-0.2% Nb, 0.01-0.1% Ti, 0.001-0.003% B, ≤0.01% N, ≤0.06% s-Al, ≤0.03% P, ≤0.03% S and the balance Fe with inevitable impurities to form a carburizing material having the thickness of an effective hardening layer of 0.4-1.1 mm. The form to the spider 18, for example, can be obtained by performing hot-forging to the steel material to obtain a formed product, carburizing and quenching, and then tempering to the formed product. COPYRIGHT: (C)2011,JPO&INPIT |
