Analysis of crack initiation in edge cracked NiTi shape memory alloy plate

Abstract

Shape Memory Alloys (SMAs) are getting more known among scientist and the engineers day by day. Therefore, their industrial, military and also daily life applications are increasing. Their unique properties make them very useful under special circumstances, however also because of that, there are some parameters (such as fracture), behaviors that need to be discovered. This thesis is designed to investigate the fracture behavior of the Shape Memory Alloys. Their super elastic behavior and martensitic transformation, especially around crack tip, is modeled on ABAQUS software followed by some MATLAB fitting evaluations in order to implement data to conventional fracture criterions. The different material properties are changed and their effects on crack angles are studied. As a result of simulations, effect of every material property and crack angle change is discussed on the last chapter. The results are interpreted as the martensitic transformation effects the crack angle according to MTS, Det and Ip crack initiation criterions due to strain hardening.