Hyperbolic Sine Representation of a Constitutive Equation for Superplastic Forming Grade Inconel 718

Abstract

The superplasticity of Inconel 718 has been reported, but there has been little development of the required constitutive relations. This paper describes the work undertaken to develop hyperbolic sine relations for superplastic forming grade Inconel 718 to represent the relationships between flow stress, strain rate and temperature over a wide range of deformation conditions. The model includes the hardening due to grain growth and the softening due to the evolution of cavitations. * * The authors would like to thank the partners involved in the MMFSC (Manufacturing and Modelling of Fabricated Structural Components) project and the European Commission for funding the work. Contract number G4RD-CT-2000-00217. www.mmfsc.net.