New Phases in a Multicomponent High Ruthenium Single Crystal Superalloy

摘要

Three unusual Ru-rich phases have been identified in a multicomponent Ni-base single crystal superalloy, including a L2_1 Ru_2AlTa Heusler phase, a B2 RuAl phase and a hcp Re(Ru)-rich δ phase. These phases have their own preferential precipitation location within the dendritic structure. No conventional topologically-close-packed (TCP) phases have been observed with thermal exposure at 950℃ for 1500 hours.