Experimental and numerical studies to estimate fatigue crack growth behavior of Ni-based super alloy

In this work, the fatigue crack growth behavior of the Nickel based super alloy is investigated at room (26 °C) and elevated temperature (650 °C). The fatigue crack growth experiments are performed to understand the effect of temperature and loading rate. The elasto plastic fracture toughness tests are performed to evaluate J IC . Paris law is used in conjunction with extended finite element method (XFEM) to numerically predict the fatigue life. The stress intensity factors of individual mode ( K I and K II ) are computed from J-integral by decomposing the stress, strain and strain derivatives into symmetric and antisymmetric parts. Few parametric studies are performed to show the mesh convergence and path independency of J-integral. Fatigue crack growth in an aero-engine turbine disc is predicted. The numerically predicted fatigue life is found in good match with the experimental results.