Unraveling the myth of closure corrections: Sharpening the definition of opening and closure stresses with an energy approach. (February 2021)

• Record Type: Journal Article
• Authors: van Kuijk, Jesse J.A.; Alderliesten, René C.; Benedictus, Rinze
• Is Part Of: International journal of fatigue. Volume 143(2021)
• Publication Date: 2021-02
• Subjects: Crack opening stress -- Crack closure -- Crack opening -- Closure corrections -- Physics based approach; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2020.106016
• Languages: English
• ISSNs: 0142-1123

Abstract

Highlights: Closure corrections and Δ K eff approach lack appropriate physical substantiation. Closure correction variations point to inconsistency of opening stress definition. Experimentally observed closure does not correspond to physical closure stress. Physics based energy method connects physical opening stress to Δ K eff . Abstract: The substantiation of fatigue crack closure corrections is disputed, based on the closure stress definition. The Δ K eff equation lacks a physical explanation. An inconsistency is observed between the opening stress S op phen as used by this equation and the physical opening stress S op phys . This S op phys is related to S op phen through an energy equivalent area approach. Furthermore, an elastic spring model is used as a physical approach to crack closure effects. An FEA approach generates S op phys values, which are reworked into S op phen . This physical model agrees well with existing closure corrections, and is able to provide a physical explanation for their necessity.