摘要
The present work introduces a novelγ’phasestrengthened Ir-W-Al-Th superalloy for ultrahigh-temperature applications.First,the as-cast microstructure and phase transformation of Ir-13 W-6 Al-0.15 Th(at%)alloy during solid solution and aging were investigated.Phase transformation was observed during heat treatment.The primaryγ’phase disappeared via the redissolution ofγ’→γat 1800℃.The recrystallization took place at 1450℃and very fine equiaxedγ’/γgrains formed after240 h.The cold-rolled microstructure indicated that the room-temperature c phase was brittle and cracks mainly emerged along grain boundaries.Ir-13 W-6 Al-0.15 Th alloy exhibited a higher nanohardness than other Ir-based superalloys and pure Ir,which can be attributed to the solid solution and precipitation(γ’)strengthening.In addition,the as-cast Ir-13 W-6 Al-0.15 Th alloy shows a medium room-temperature compressive yield strength and good ductility.
出处
《Rare Metals》
SCIE
EI
CAS
CSCD
2021年第12期3588-3597,共10页
稀有金属（英文版）
基金
financially supported by the fund of the National Key R&D Program of China(No.2017YFB0305500)
the State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals(No.SKL-SPM-2018010)。
