Fatigue crack growth prediction for small-scale yielding (SSY) and non-SSY conditions. (October 2020)

• Record Type: Journal Article
• Authors: Cheng, Ankang; Chen, Nian-Zhong; Pu, Yongchang; Yu, Jianxing
• Is Part Of: International journal of fatigue. Volume 139(2020)
• Publication Date: 2020-10
• Subjects: Fatigue crack growth (FCG) -- J-integral -- Elastic-plastic fracture mechanics (EPFM) -- Energy balance -- Small-scale yielding (SSY) and non-SSY conditions; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2020.105768
• Languages: English
• ISSNs: 0142-1123

Abstract

Highlights: Δ J is applied based on a rearranged fatigue crack growth (FCG) process. Governing equation of global energy balance is derived to calculate the FCG rate. FCG over whole Δ J regime for small-scale yielding (SSY) conditions is predicted well. Stable FCG for both SSY and non-SSY conditions is predicted well. Only fundamental deformation properties are required as material inputs. Abstract: A model to predict fatigue crack growth (FCG) for small-scale yielding (SSY) and non-SSY conditions where J -integral applies is established. The Δ J -characterized elastic-plastic fracture mechanics (EPFM) analysis is performed based on a rearranged FCG process to achieve the crack-tip geometry and stress state. The root stress of blunted crack and the FCG rate are calculated from the cycle-wise local and global energy balance. To consider effects of geometry, load level and strain hardening, a correction factor is further developed in the governing equation of global energy balance. The model is validated using the test data of several types of metals.