Analysis on interfacial debond crack of SRM

By means of finite element method, the finite singular crack elements were arranged around the crack tip to simulate the singularity near crack tip. Aiming at the axisymmetric interface debond crack on the motor head, the stress intensity factors of different depth cracks between liner and grain, case and insulation were calculated under internal ignition pressure. The development law of the stress intensity factors with crack depth was pointed out. The results show that interface crack between liner and grain is in close state, and the stress intensity factors hardly change when crack depth is small. With the increase of crack depth, crack starts to open, and the stress intensity factors in the crack tip continuously increase. The interfacial crack between case and insulation is always in open state, moreover the stress intensity factors increase with the crack depth.