Low-cycle fatigue fracture in metallic alloy materials with mutiple internal cracks

• Main Author: Chen, Yali
• Other Authors: Xiao Zhongmin
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2021
• Subjects: Engineering::Mechanical engineering
• Online Access: https://hdl.handle.net/10356/150331
• Institution: Nanyang Technological University

For failure analysis and prevention of various engineering materials and structures, the advanced finite element method (XFEM) and cohesive force (Cohesive) model have been widely used to simulate the random cracks in those materials and structures. In the current project, the cohesion model is used to simulate the propagation of a random crack in metallic alloy materials. In order to analyze the influence of inclusions (embedded in those materials) and their material properties on the crack propagation path, the propagation of the crack in the symmetrical inclusion region is simulated. The situation of a crack penetrating into or bypassing an inclusion in certain cases has been simulated and analyzed. This report introduces four simulation and analysis categories, including:  A single crack interacting single metal inclusion in an infinite sheet with different interfaces. Computational examples are given for different inclusion/ matrix elastic modulus ratios and a different number of cycles of load period.  Two Symmetric cracks and a single metal inclusions interaction case.  A single crack and the symmetrical metal inclusions interaction case.  The multiple cracks and the multiple metal inclusions interaction case. Base on the data obtained through simulation and analysis, various parameters influencing the fatigue life of the materials and structures have been analyzed.