Abstract
The precipitation kinetics of γ'-Ni3(Al,Ta)phase and creep properties of Ni-15Al-xTa at.％superalloys are investigated by the crystal plasticity phase-field simulation.The results show that the high Ta content brings a lower creep strain for the deceleration and steady creep stage,while the creep lifetime is shorter.The large external strain intensifies the creep damage and shortens the creep life of Ni-15Al-3Ta at.％superalloy.The kinetics evolution and elements distribution are revealed in the quaternary Ni-10Al-8.5Cr-xTa(x=1.5 at.％,2.0 at.％,2.5 at.％)superalloys by the multi-component phase-field simulation.The anti-phase boundary(APB)changes the coarsening mechanism of γ'phase,and Ta promotes the precipitation of γ'phase with an increasing volume fraction and particle number.The composition difference between γ'and γ phases increases with the rising of Ta content,the strong partitioning of Ta to γ'phase strengthens the partitioning of Ni and Cr to γ matrix,and Ta shows a superiority than Al in the lattice site occupation of L12-Ni3(Al,X)phases.As an important γ'phase forming element,the optimization of Ta content is essential for improving the mechanical properties of Ni-based superalloys.
基金项目
国家自然科学基金(52275342)
中央高校基本科研业务费专项(30921013107)
维普
万方数据