Effect of surface flaw on fatigue strength of shot-peened medium-carbon steel. (January 2015)

• Record Type: Journal Article
• Authors: Sakamoto, Junji; Lee, Yong-Sung; Cheong, Seong-Kyun
• Is Part Of: Engineering fracture mechanics. Volume 133(2015)
• Page Start: 99
• Page End: 111
• Publication Date: 2015-01
• Subjects: Fatigue strength -- Shot peening -- Surface flaw -- Small fatigue crack behavior -- Focused ion beam; Fracture mechanics -- Periodicals; Rupture, Mécanique de la -- Périodiques; Fracture mechanics; Periodicals; 620.112605
• DOI: 10.1016/j.engfracmech.2014.11.005
• Languages: English
• ISSNs: 0013-7944

Abstract

Highlights: Effect of surface flaw on fatigue strength of shot-peened steel was studied. Initial cracks were observed on the surface after shot peening treatment. The fatigue fracture occurs by the propagations and coalescences of initial cracks. The fatigue limit was determined by the crack propagation limit. The small flaws have not notably reduced the fatigue strength of shot-peened steel. Abstract: The effect of surface flaw on fatigue strength of shot-peened medium-carbon steel was experimentally studied. The fatigue crack initiation life, fatigue crack growth life, and fatigue limit in the steel can be increased by using shot peening (SP). The fatigue fracture of SP specimen occurred by the propagations and coalescence of fatigue cracks initiated from the initial cracks due to SP. The fatigue limit of SP specimen was determined by the propagation limit of fatigue crack. When the size of surface flaw is sufficiently small compared to the SP affected zone, the flaws have not significantly changed the fatigue strength of the SP specimens.