| 摘要 |
PROBLEM TO BE SOLVED: To provide a steel for induction hardening, capable of providing machine parts, such as gear, shaft, and uniform velocity joint for automobile, excellent in bending fatigue characteristic and rolling fatigue characteristic by means of induction hardening. SOLUTION: This steel is composed of a linear or bar-shaped rolled steel stock. In the longitudinal cross section passing through the axis of this rolled steel stock, the number of multiple inclusions of oxide and sulfide of >=10μm average grain size, existing in the inspection area of 100 mm<2> containing, as a center line, a virtual line parallel to the axis and apart from the axis by 1/4.D (where D means the diameter of the rolled stock), is regulated to <=20 pieces. This steel can produce excellent bending fatigue strength and rolling fatigue strength by being subjected to induction hardening.
|
