ABSTRACT
Equation 1 represents the functional form for the crack propagation rate with four constants γ1, γ2, γ3, γ4. These coefficients are determined using the experimental data. The best suited values of the coefficients to the experimental data γ1, γ2 and γ3 are obtained as 1.21, 4.29 and −0.968 respectively. The coefficient γ3 corresponds to the elastic mismatch parameter which depends on the type of interface. A linear relationship as shown in Figure 1 is proposed between the mismatch parameter of the interface specimen and the corresponding coefficient is expressed as, γ3 = P1α + P2. The values of P1 and P2 are 129.19 and 1.27 respectively.
