The applicability of various fracture parameters such as J-integral, and rate of crack tip opening displacement as a parameter which controls the creep crack growth behavior is investigated by performing creep tests on STS 316 stainless steel and STS 304 stainless steel at 625℃ and 600℃ respectively. The results obtained may be summarized as follows;
(1) the creep crack growth rate of both materials is well described by either the C - integral or the rate of crack tip opening displacement ;
(2) the creep fracture resistance of STS 316 stainless steel is higher than that of STS 304 stainless steel.