Abstract
Directionally solidified Ni-base superalloy have been developed as a gas turbine blade for high efficiency thermal power plant. Gas turbine blades are used under the conditions of high temperature creep. It is considered that creep crack growth behavior and its life of directionally solidified Ni-base superalloy will be affected by crystal orientation around a crack, since directionally solidified Ni-base superalloy has different crystal orientation. In this study, in order to clarify the scatter of crack growth life of directionally solidified Ni-base superalloy, the designed two-dimensional elastic-plastic creep finite element analyses were conducted to clarify the effect of crystal orientation on creep crack growth.