Optimization of pressure and soaking time of HIP treatment on 713LC cast superalloy

Abstract

This paper discusses the effect of pressure and soaking time of HIP on 713LC cast superalloy. In this study, the HIP temperature was kept at 1453 K. Two different pressures, 150 and 175 MPa, were applied, and the soaking times were 2 and 4 h. The results of the experiment showed that the HIP treatment for 713LC superalloy at the temperature of 1453 K, pressure of 175 MPa, and soaking time of 2h yielded the optimal results. Porosity was decreased to 60.3%. At fast strain rate (0.001 s-1), it increased the tensile strength by 8.8% at 298 K, 13% at 813 K, and 13.6% at 923 K. The elongation increased 32.9% at 298 K, 21.6% at 813 K, and 99.5% at 923 K in the tension tests. The treatment also increased the strength by 10% at 298 K and 17% at 813 K in the bending test. HIP treatment was proven to enhance the MC carbide precipitation on grain boundary, improve the grain size and the uniformity of size, and decrease the segregation phenomenon of 713LC casting. © 2009 The Japan Institute of Metals.