Effect of Two Heat Treatment Processes on Microstructures and Tensile Behaviors of Ni-Based Superalloy K465

Abstract

The effect of two heat treatment processes on microstructures and tensile behaviors of K465 superalloy was investigated and compared. The results show that hot isostatic pressing (HIP) process partly or completely eliminated the micro-porosity to densify K465 alloy, and can effectively reduce the size of γ′ phase and improve the tensile strength and plasticity of K465 alloy. Electron probe micro-analysis (EPMA) studies revealed that the element segregation ratio was smaller in the HIP process alloy than that in the ordinary process alloy. nanoindentation tests revealed that elastic modulus and the hardness in the interdendrite of K465 alloy for HIP process were higher than that for the ordinary process.

Microstructure degradation and residual low cycle fatigue life of a serviced turbine blade

“…The larger the ξ , the higher the degree of degradation. The initial width of the γ phase is generated from the previous publication 39 …”

“…The initial width of the γ phase is generated from the previous publication. 39 Figure 10 shows a comparison of microstructural indicator, ξ, of the airfoils for the blade serviced at different duration. The distributions of microstructural indicator for different serviced turbine blades are similar to that of γ matrix.…”