Influence of inclusion on the stress intensity factors under thermomechanical loads in a PM superalloy

The interaction between a round inclusion and a crack under thermomechanical loading is analyzed based on a modified body force method. The traction-free condition on the crack line is mended by adding the resultant force induced by thermal stress to the force equilibrium equations, so that the coupling of mechanical and thermal loads could be taken into account. The series of integral equations can be discretized to a set of linear equations. Stress intensity factors (SIFs) are obtained through solving the linear equations. The calculated results in this paper are compared to those in open references to validate the method and code. The method is applied to a case of FGH95 PM superalloy containing Al2O3 inclusions under mechanical and thermal loads. The results show that the thermal load has little effect on SIF, while the mechanical load is the dominant factor.