Modeling the flow curves of materials at elevated temperatures is the first step in mathematical simulation of the hot deformation processes of them. In this work a comparative study was provided to examine the capability of three different constitutive equations in modeling the hot deformation flow curves of AZ91 magnesium alloy. For this, the Arrhenius equation with strain dependent constants...

To investigate the hot deformation behavior of 17-7 PH stainless steel, hot compression tests were carried out at the temperatures of 950, 1050 and 1150 oC and strain rates of 0.001 s-1 to 0.1 s-1. Accordingly, the hot working behavior was studied by the analyses of flow stress curves, work hardening rate versus stress curves, exponent- type constitutive equations and deformed microstructures. ...

3 Constitutive equations 18 3.1 Phenomenological constitutive equations . . . . . . . . . . . . 18 3.2 Curie Principle . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.3 Onsager relations . . . . . . . . . . . . . . . . . . . . . . . . . . 20 3.4 Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 3.5 Minimum Entropy production . . . . . . . . . . . . . . . . . . 25

We first write down a very general description of nonlinear classical electrodynamics, making use of generalized constitutive equations and constitutive tensors. Our approach includes non-Lagrangian as well as Lagrangian theories, allows for electromagnetic fields in the widest possible variety of media (anisotropic, piroelectric, chiral and ferromagnetic), and accommodates the incorporation of...

Mechanical behavior of the Space Shuttle redesigned solid rocket motor (RSRM) propellant is studied from a phenomenological point of view. Motivated by the study of the experimental data three initially isotropic constitutive models have been developed. All models represent the e ect of strain rate, superimposed hydrostatic pressure, and cyclic loading on the stress and dilatation response of t...