Steel for carbonitrided bearing

US10538832B2 · kind B2 · utility

Assignees

• NIPPON STEEL CORPORATION · JP
• JTEKT CORPORATION · JP

Inventors

• Yutaka Neishi · Tokyo, JP
• Takahisa Suzuki · Kawasaki, JP
• Tatsuya Koyama · Kyoto, JP
• Shingo Yamasaki · Tokyo, JP
• Kohei Kanetani · Kashiba, JP
• Takashi Sada · Osaka, JP

Key dates

• Filing date: Jul 29, 2015
• Grant date: Jan 21, 2020
• Expiry date: Jul 29, 2035

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16C2240/90
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Provided is a steel for carbonitrided bearing which excels in hardenability and also excels in toughness, wear resistance, and surface-originated flaking life after quenching and tempering. A steel for carbonitrided bearing of the present embodiment has a chemical composition containing, in mass %, C: 0.22 to 0.45%, Si: not more than 0.50%, Mn: 0.40 to 1.50%, P: not more than 0.015%, S: not more than 0.005%, Cr: 0.30 to 2.0%, Mo: 0.10 to 0.35%, V: 0.20 to 0.40%, Al: 0.005 to 0.10%, N: not more than 0.030%, and O: not more than 0.0015%, with the balance being Fe and impurities, and satisfying Formulae (1) and (2). 1.20<0.4Cr+0.4Mo+4.5V<2.60  (1)2.7C+0.4Si+Mn+0.8Cr+Mo+V>2.20  (2)