The alloying effects of Ni,W and Cron the microstructural stability of CoNi-base alloys were investigated using a multicomponent diffusion multiple after being aged at 1000℃ for 1000 h.The diffusion multiple was care...The alloying effects of Ni,W and Cron the microstructural stability of CoNi-base alloys were investigated using a multicomponent diffusion multiple after being aged at 1000℃ for 1000 h.The diffusion multiple was carefully designed based on thermodynamic calculations.The relationships between alloy compositions and microstructural characteristics were established over a large compositional range using this single sample,and the alloying effects of Ni,W and Cron the elemental partitioning behaviors betweenγ and γ' two phases were thermodynamically analyzed using high-throughput calculation.The results together show that an increase of Ni content increases the γ' volume faction in the long-term aged microstructures.However,the higher Ni content leads to the precipitation of the χ phase by promoting the partitioning of W from the γ' phase to the γ phase.The decrease of W content dramatically reduces theγ' volume faction,but the addition of Cr can properly counteract this effect by promoting the partitioning of Al and Ti from the γ phase to the γ' phase.This study will be helpful for accelerating the development of novel γ'-strengthened multicomponent CoNi-base alloys,as well as providing experimental data to improve the thermodynamic database.展开更多
基金supported by the National Key Research and Development Program of China(No.2017YFB0702902)the National Natural Science Foundation of China(No.51771019)the Guangdong Province Key Area R&D Program(No.2019B010943001)。
文摘The alloying effects of Ni,W and Cron the microstructural stability of CoNi-base alloys were investigated using a multicomponent diffusion multiple after being aged at 1000℃ for 1000 h.The diffusion multiple was carefully designed based on thermodynamic calculations.The relationships between alloy compositions and microstructural characteristics were established over a large compositional range using this single sample,and the alloying effects of Ni,W and Cron the elemental partitioning behaviors betweenγ and γ' two phases were thermodynamically analyzed using high-throughput calculation.The results together show that an increase of Ni content increases the γ' volume faction in the long-term aged microstructures.However,the higher Ni content leads to the precipitation of the χ phase by promoting the partitioning of W from the γ' phase to the γ phase.The decrease of W content dramatically reduces theγ' volume faction,but the addition of Cr can properly counteract this effect by promoting the partitioning of Al and Ti from the γ phase to the γ' phase.This study will be helpful for accelerating the development of novel γ'-strengthened multicomponent CoNi-base alloys,as well as providing experimental data to improve the thermodynamic database.
