Effect of shear-affected zone on fatigue crack propagation mode. (November 2018)

• Record Type: Journal Article
• Authors: Hamada, Shigeru; Zhang, Kejin; Zhang, Jiwang; Koyama, Motomichi; Yokoi, Tatsuo; Noguchi, Hiroshi
• Is Part Of: International journal of fatigue. Volume 116(2018)
• Page Start: 36
• Page End: 47
• Publication Date: 2018-11
• Subjects: Fatigue limit -- Shear-affected zone -- Fatigue crack propagation -- Mode II fatigue; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2018.06.003
• Languages: English
• ISSNs: 0142-1123

Abstract

Highlights: Effect of a shear-affected-zone (SAZ) on fatigue limit was investigated. Tests on specimens with and without SAZ were conducted. Propagation resistance of the fatigue crack has been lost by the punching process. Fatigue crack growth mode had a possibility of transition from Mode I to Mode II. Fatigue limit design for the punching processed plate was coarse-grained. Abstract: It is well known that the fatigue limits of some precipitation-hardened steels with a punched hole do not increase, even if the tensile strengths of base-metal increases. This study suggested that the dominant reason for this strange phenomenon is a transition from the Mode I type fatigue crack propagation due to the cyclic plastic deformation to Mode II type propagation due to the damage accumulation by a quantitative analysis of influential factors based on fracture mechanics. This result can open a probability that the fatigue limit of the punched hole with shear-affected zone can be actively quantified.