Singularity Of Cavitation Shotless Peening Compared With Shot Peening

Author:  H. Soyama
Source:  Conf Proc: ICSP-10 Tokyo, Japan 2008
Doc ID:  2008051
Year of Publication:  2008
Abstract:  
ABSTRACT Cavitation impacts, which are normally causes severe damage in hydraulic machinery, can be utilized for peening instead of impacts induced by collision of shots. Peening method using cavitation impacts is named as cavitation shotless peening, as shots are not required. In the present paper, mechanism of cavitation shotless peening including how to generate cavitation bubbles and its optimization was presented, and singularity of cavitation shotless peening compared with shot peening was discussed by investigating the peened surface using X-ray diffraction method. It was revealed experimentally that full width at half maximum FWHM of Xray diffraction from surface treated by cavitation shotless peening was decreased, although FWHM from shot peened surface increases. It means that cavitation shotless peening released micro-strain which was introduced by machine finishing and heat treatment, although cavitation shotless peening introduced compressive residual stress in the materials. KEY WORDS Residual stress, Fatigue strength, X-ray diffraction, Cavitation