Research on the microstructure evolution of Ni-based superalloy cylindrical parts during hot power spinning

摘要

To predict the microstructure evolution and reveal the forming mechanism of Ni-based superalloy cylindrical parts during hot power spinning,a finite element method (FEM) model of deformation-heat transfermicrostructure evolution was established using MSC.Marc software.A numerical simulation was then conducted based on the secondary development of user subroutines,to investigate evolution of the microstructure of a Haynes 230 alloy cylindrical part during hot power spinning.The volume fraction of dynamic recrystallization (DRX) and the grain size of Haynes 230 alloy cylindrical parts during hot power spinning were analyzed.The results showed that the DRX of the spun workpiece was more obvious with an increase in the forming temperature,T,and the total thinning ratio of wall thickness,ψt.Furthermore,the complete DRX microstructure with fine and uniform grains was obtained when T ≥ 1 100 ℃ and ψt ≥ 56％,but the grain size of the spun workpiece decreased slightly with an increase in the roller feed rate,f.The experimental results conformed well with simulation results.