Behavior of Creep Crack Growth and Its Simulation from the Standpoint of Crack Energy Density

Abstract

The general condition by which the rate of crack growth is controlled is discussed based on the concept of crack energy densityε, and especially the parameters of creep crack growth rate are proposed, that is, it is shown that the average values of ∂^^∼ε_t/∂t, ∂^^∼ε_x1/∂X₁ concerning withεwhich correspond to the increase rate and the gradient ofεat the crack tip respectively are the parameters of creep crack growth rate based on the creep crack model in which a crack extends discontinuously with respect to time. And the crack growth of center notched specimen in tensile creep under plane stress condition is simulated by means of Finite Element Method. In the analysis, the condition of constantε_c(critical value ofε) is used. The validities of ∂^^∼ε_t/∂t, ∂^^∼ε_x1/∂X₁ as parameters of creep crack growth are numerically verified through this analysis.