Johnson-Cook constitutive equation is one of the most famous constitutive equations that have ever been developed to model the hot deformation flow curves of different materials. This equation is a predefined model in the traditional finite element codes to describe the material behavior in applications such as simulating the manufacturing processes. In this work, two different genetic algorith...

Till now, different constitutive models have been applied to model the hot deformation flow curves of different materials. In this research, the hot deformation flow stress of API X65 pipeline steel was modeled using the power law equation with strain dependent constants. The results was compared with the results of the other previously examined constitutive equations including the Arrhenius eq...

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...

Even though applications of direct numerical simulations are on the rise, today most usual method to solve turbulence problems is still apply a closure scheme defined order. It not case that rising order model always related quality improvement. more, conceptual advantage applying lowest it represents analogous procedure introducing constitutive equation which has brought success many other are...

the main contribution of the present work is to investigate the capability of exponential-type constitutive equationto model the warm deformation flow curves of a eutectoid steel in the temperature range of 620-770 °c andat the strain rates in the range of 0.01-10 s-1 conducted on a gleeble-1500 thermomechanical simulator. warmdeformation in this temperature range facilitates the occurrence of ...

Based on the recently introduced fractional Taylor’s formula, a fractional heat conduction constitutive equation is formulated by expanding the single-phase lag model using the fractional Taylor’s formula. Combining with the energy balance equation, the derived fractional heat conduction equation has been shown to be capable of modeling diffusion-to-Thermal wave behavior of heat propagation by ...

I calculate the hydrodynamic limit of the BGK approximation of the Boltzmann equation for the case of a long stress relaxation time and find that the stress obeys a viscoelastic constitutive equation. The constitutive equation is different from standard constitutive equations used for polymeric liquids in that it is not “objective” because inertial effects are important. I calculate the exact s...