Effects of the Intermediate Aging Condition on the Precipitation of η Phase and Mechanical Properties of Iron-Base Superalloy V57

Abstract

Effects of the intermediate aging condition on the cellular precipitation of 72 phase at grain boundary and mechanical properties of an iron base super alloy, V 57 have been investigated and the relation ship between the amount of η phase and mechanical properties has been discussed.
η phase increases with the increase of intermediate aging temperature and time, and decreases withraising preheating temperature before the intermediate aging because of γ′ precipitation during preheating.
Grain boundary η phase has little effect on tensile strength at room temperature. The increase ofgrain boundary η phase causes slight decrease of tensile elongation at room temperature, remarkabledecrease of stress rupture life and also remarkable increase of stress rupture elongation.