Fatigue Crack Growth Analysis of Functionally Graded Materials by EFGM and XFEM

The present work investigates the fatigue life of a functionally graded material (FGM) made of aluminum alloy and alumina (ceramic) under cyclic mixed mode loading. Both element free Galerkin method (EFGM) and extended finite element method (XFEM) are employed to simulate and compare the fatigue crack growth. Partition of unity is used to track the crack path in XFEM while a new enrichment criterion is proposed to track the crack path in EFGM. The fatigue lives of aluminum alloy, FGM and an equivalent composite (having the same composition as of FGM) are compared for a major edge crack and center crack in a rectangular domain. The proposed enrichment criterion not only simulates the crack propagation but it also extends the applicability and robustness of EFGM for accurate estimation of fatigue life of component.