Study of Dynamic Fracture of Functionally Graded Materials under Thermo-mechanical Shocks

In this paper fracture behavior of functionally graded materials under thermo-mechanical shocks is investigated. For this purpose classical coupled thermoelastic equations are used in the calculations. These equations are discretized with extended finite element method and then are solved by the Newmark method in the time domain. Micromechanical models for conventional composites are used to estimate properties of FG layers. The most general form of interaction integral is extracted for moving cracks in FGMs under thermo-mechanical loadings، and then it is employed to calculate the stress intensity factors at each time step. All stages of problem solution from mesh generation to obtaining results were implemented in MATLAB programming environment. Some examples are solved and obtained results are compared with existing analytical and numerical results in other papers. Good accordance between these results verifies presented method and written code in this paper. Finally the effects of material properties profile variation on dynamic stress intensity factors in a glass/epoxy beam under thermo-mechanical shocks are investigated. Also crack propagation path and speed are studied for this beam.