Investigation of the Heat Treatment Effect on Microstructures and Phases of Inconel 713C Superalloy

Abstract

The application of Inconel 713C is very vast in different industries such as in automobiles, aircrafts, boilers and turbines. In this paper, Inconel 713C specimens were solutionized at 1000 and 1200 °C for 1 hours in order to study changes in phases and the structure of alloy to modify the γ' phase. The optical and the scanning electron microscopy were used to investigate the structure and the energy dispersive spectroscopic (EDS) and the X-ray diffraction (XRD) were applied to identify the composition and phase changes. Results showed that the solutioning heat treatment at 1000 °C for 1 hour caused to participate Cr23C6, but when the temperature of heat treatment increased to 1200°C, chromium carbides solutionized in the γ matrix. Besides, by applying the heat treatment at temperature of 1000 °C, the γ' phase dissolved in (200) and (220) plane and this phase in the plane of (111) had the best stability. However the (220) plane of γ' phase was stable thermodynamically for the specimen without the heat treatment. Phases of Ni5Al3 and Al0.42Ni0.58 were observed at the temperatures of 1000 and 1200 °C, respectively. In addition, as the heat treatment temperature increased from 1000 to 1200 °C the new phase of AlNi3C0.5 solutionized in the γ matrix.