A modification of UniGrow 2‐parameter driving force model for short fatigue crack growth. Issue 1 (19th June 2018)

• Record Type: Journal Article
• Authors: Bang, D.J.; Ince, A.; Tang, L.Q.
• Is Part Of: Fatigue & fracture of engineering materials & structures. Volume 42:Issue 1(2019)
• Page Start: 45
• Page End: 60
• Publication Date: 2018-06-19
• Subjects: fatigue crack growth rates -- high cycle fatigue -- long crack -- short crack -- stress intensity factor -- UniGrow model; Materials -- Fatigue -- Periodicals; Fracture mechanics -- Periodicals; 620.1123
• DOI: 10.1111/ffe.12865
• Languages: English
• ISSNs: 8756-758X

Abstract

Abstract: In this paper, a modification of the UniGrow model is proposed to predict total fatigue life with the presence of a short fatigue crack by incorporating short crack propagation into the UniGrow crack growth model. The UniGrow model is modified by 2 different methods, namely the "short crack stress intensity correction method" and the "short crack data‐fitting method" to estimate the total fatigue life including both short and long fatigue crack propagations. Predicted fatigue lives obtained from these 2 methods were compared with experimental data sets of 2024‐T3, 7075‐T56 aluminium alloys, and Ti‐6Al‐4V titanium alloy. Two proposed methods have shown good fatigue life predictions at relatively high maximum stresses; however, they provide conservative fatigue life predictions at lower stresses corresponding high cycle fatigue lives where short crack behaviour dominates total fatigue life at lower stress levels.