Nippon Steel Sumitomo Metal Corporation

Hiroki Uekita

Yutaka Neishi

Shinichirou Kashiwagi

Takefumi Yano

Tetsurou Hirano

Toshikazu Saitou

A roughly shaped material for a rolling bearing of the present invention is produced by forging a steel composed of a high-carbon chrome bearing steel containing 0.7 mass % to 1.2 mass % of a carbon, and 0.8 mass % to 1.8 mass % of a chromium to a predetermined shape while heating the steel to a forging temperature in a range of (Aepoint+25&#xb0; C.) to (Aepoint+105&#xb0; C.), cooling a forged article to a temperature of Aepoint or lower, and performing an annealing in which the forged article that is obtained is heated to a soaking temperature in a range of (Aepoint+25&#xb0; C.) to (Aepoint+85&#xb0; C.), the forged article is retained for 0.5 hours or longer, and the forged article is cooled down to 700&#xb0; C. or lower at a cooling rate of 0.30&#xb0; C./s or slower.

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Lexington, KY, United States of America

Hiroki Uekita