Analysis of Flow Stress Behaviour of Inconel Alloys at Elevated Temperatures Using Constitutive Model

Abstract

A reliable and accurate prediction of flow behaviour of metals considering the coupled effects of strain, strain rate and temperature is vital in analyzing the workability of the metal. In this study, Khan-Huang-Liang (KHL) phenomenological based constitutive models has been developed for flow stress prediction of Inconel 625 and 718 alloys. Firstly, uniaxial tensile tests have been performed from room temperature to 400°C at an interval of 100°C and slow strain rate ranges of 0.0001-0.01s-1. KHL constitutive model has been developed using uniaxial tensile test data. The predicted flow behaviour has been compared with experimental stress-strain data. The prediction capability of these models has been verified using various statistical measures such as correlation coefficient (R), average absolute error (Δ) and its standard deviation (S). Based on the analysis of statistical measures revealed that KHL model has good in agreement with experimental flow stress behaviour.