Development of Cavitation Peening in Water for Improvement in Rolling Contact Fatigue Life of Case-Hardened Steel

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K05775
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Design engineering/Machine functional elements/Tribology
• Research Institution: Okayama University of Science
• Principal Investigator: SEKI Masanori 岡山理科大学, 工学部, 准教授 (10314650)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 機械要素 / 疲労 / 表面処理

Outline of Final Research Achievements

The rolling contact fatigue lives of the case-hardened steel became longer as the processing time of the cavitation peening became longer under a processing time of 30 minutes or shorter. In particular, the rolling contact fatigue lives of the case-hardened steel were improved to about 7 times by the cavitation peening with a processing time of 30 minutes. Moreover, a cavitation peening apparatus was newly built by using a plunger pump with a maximum injection pressure of 35 MPa. As a result, the processing capacity of the cavitation peening under an injection pressure of 35 MPa was triple of that under an injection pressure of 20 MPa.

Free Research Field

機械設計学

Academic Significance and Societal Importance of the Research Achievements

本研究の成果として，浸炭硬化鋼の転動疲労寿命がキャビテーションピーニングによって向上することを初めて実証した．すなわち，軸受の転動疲労寿命向上にキャビテーションピーニングを適用することができることを明らかにした．さらに噴射圧力20MPaの場合に比べ，噴射圧力35MPaの条件下でのキャビテーションピーニングの加工能力は約3倍に達したことから，キャビテーションピーニングが転動疲労寿命を飛躍的に向上させることができると期待される．