Abstract
High temperature fatigue crack growth tests under multiaxial stress conditions were conducted for SUS304 stainless steel. By using DC electrical potential drop (PD) method, multiaxial crack growth was evaluated. Under the conditions, two types of fatigue crack growth were observed; "tensile type" crack, which propagates along the direction, φ, perpendicular to the maximum principal stress, σ_1 and "shear type" crack, which propagates along the direction of maximum shear stress, T_<max>. For each crack growth type, cyclic response of deformation during fatigue tests and micrographs of the fracture surface were examined. From these results, crack growth mechanisms were discussed.