Transient thermoelastic responses of functionally graded materials containing collinear cracks

A generalized method to treat the collinear cracks in functionally graded materials (FGMs) subjected to thermal loads is established. The integral transform technique is used to reduce the problem to a set of singular integral equations which is solved numerically. A metal/ceramic FGM plate and a metal layer/ceramic layer bonded plate are analyzed as examples. Numerical results are obtained to show the influence of crack spacing on field intensity factors ahead of the crack-tips. It is observed that thermal stress intensity factors can increase or decrease with the crack spacing. Through the introduction of the FGM, the thermal stress intensity factors can be reduced.