Abstract
Thermal stress field around contact faces was analyzed by FEM to understand the crack propagation across contact faces. Stress singularities disappear when the crack tip reaches to the contact face. For the continuous growth, new edge crack must be created at the opposite face. Frictional forces acting on the contact faces restrain the crack creation until the propagating crack tip reaches the face. Then the frictional forces act oppositely to increase the normal stress acting parallel to the face at the crossing point. Suitable situation is achieved for the crack creation at the opposite face. Experimentally, cracking was observed at the contacting faces against continuous face and separated faces. Crack timing and position were well in accord with the analysis.
