Improvement Of Bending Fatigue Limit By Cavitation Peening For Carbon Steel Specimens Containing An Artificial Surface Defect

Author:  Fukuda, Matsui, Ishigami, Amano, Takahas, Ando
Source:  Conf Proc: ICSP-10 Tokyo, Japan 2008
Doc ID:  2008055
Year of Publication:  2008
Abstract:  
ABSTRACT It is well known that surface defects such as surface cracks and non-metallic inclusions are decreased the fatigue strength of vehicle parts. However, the study on overcoming the surface defects by using surface refining methods is hardly reported. The cavitation peening (CP) method is in the limelight as a new possible surface refining method, which is a shot-less peening method and increases compressive residual stress. On studying the effects of the CP to the defects, the authors conducted an experiment using the two types of specimens with an artificial semicircular slit, whose slit diameter (2a)=0.08, 0.15 and 0.20mm on the surface of specimens, and evaluated their refined surface characteristics and fatigue limits. The results obtained are: 2a of the acceptable defect with the smooth and that with notched specimens were 0.08 and 0.15mm, respectively. Key Word: Fatigue, Cavitation, Peening, Steel, Defect, Residual stress