Effect of Hot Isostatic Pressing on the Tensile Property of a Second Generation Single Crystal Superalloy

Abstract

The hot-isostatic pressing (HIP) process at the condition of 1300 °C/100 MPa, 4 h was applied on the second generation single crystal superalloy DD6. Microstructural evolutions of DD6 alloy after HIP and heat treatment were observed by using optical microscope (OM), scanning electron microscope (SEM) and electron probe micro-analyzer (EPMA). The tensile properties of DD6 alloy after HIP treatment were tested at 760 and 980 °C. The results showed that the volume fraction of porosity in DD6 alloy deceased from 0.31 to 0.04% after the HIP treatment of 1300 °C/100 MPa, 4 h, meanwhile, the dendritic segregation was homogenized gradually. Compared to the standard heat treatment, the HIP treatment did not change the tensile strength and elongation of DD6 alloy at 760 °C obviously. While the elongation of DD6 alloy increased from 24.25 to 35.90% at 980 °C.