Fracture mechanisms of ceramic coating during wear

A typical buckling phenomenon of the coating on the wear groove caused by the residual compressed stress was analyzed by the interface fracture mechanics and the buckling theory. It has been found that there is a critical thickness of coating on the wear groove for the buckling. The critical thickness can be calculated by t(b)/c(d) = [12(1 - v(f)(2))sigma(R)/pi(2)E(f)](1/2) (here t(b) is the coating thickness, c(d) the length of the interfacial crack, v(f) the Poisson's ratio of the coating, sigma(R) the residual compressed stress in thecoating, and Ef( )the elastic modulus of the coating).