Rupture Life of Materials Obeying Exponential and Power Law Creep

抄録

Based on the void growth and damage mechanics, the rupture time t_r is derived as a function of the creep exponent n and the reference stress σ_o and the corresponding time t_o, for materials obeying exponential and power law creep. The analysis is extended to obtain parameters for prediction of long time behaviour. For materials which obey a simple power law creep, the parameter is shown as P=log t_r+(n- n_r)log(1-D_c) and for materials which obey an exponential function the parameter is given as P=log t_r+(n_r-n) D_c where n_r is the reference creep exponent and D_c is the critical size of the void at fracture, which is related to the applied stress σ as D_c=1-σ/σ_o