Subinterfacial cracks in bimaterial systems subjected to mechanical and thermal loading

The effect of temperature on the propagation paths of subinterfacial cracks is studied. An aluminum/polymethyl-methacrylate bimaterial specimen with large mechanical and thermal mismatches is used to investigate the effect of combined thermal and mechanical loads. The stress intensity factor (SIF) generated by mechanical loading in the presence of a temperature gradient is obtained by means of experiment and analyzed using the finite element method. A full-field optical shearing interferometry technique was used to measure the crack tip stress state. The results show that thermal effects can alter the SIFs sufficiently large enough to change the fracture behavior of subinterfacial cracks. (C) 2001 Elsevier Science Ltd. All rights reserved.