BEHAVIOR OF GAS-TURBINE BLADE MATERIALS U NDER LONG-TERM CREEP-FATIGUE LOADING

The long-term creep fatigue behaviour of the gas turbine blade materia l IN-738 LC HIP is investigated by a service-type strain cycle up to a test duration of about 12 000 h. Further, it is reported about shorte r tests of the same type on alloy IN-100 HIP The cyclic deformation of alloy IN-738 LC HIP in the long-term region is analysed and the creep fatigue crack initiation is described by the generalized damage accum ulation rule using two different methods.