Assessment on the thermo-mechanical fatigue properties of 98 Ni-base single crystal superalloys

Thermo-mechanical fatigue (TMF) property data generated in NIMS on 1st to 5th generation single crystal (SC) superalloys have been analyzed to understand the compositional and structural factors affecting the property. It was found that Re and Ru additions effectively improve the out-of-phase TMF property. The optimum γ′ fraction was found to be about 74%. A prediction equation for the TMF life from a given chemical composition has been derived for designing further superior SC superalloys.