During most metal manufacturing processes, the medium deforms by generating large quantities of plastic strain at relatively high strain rates, inevitably inducing rises in temperature. Metals characterized by low thermal conductivity properties might locally retain high temperatures, consequently undergoing thermal softening. The classical balance laws governing the continuum equilibrium show severe mesh sensitivity if they were numerically discretized through finite element methods. Furthermore, the plastic deformation tends to localize in narrow areas whose characteristic length is comparable to grain size, thereby requiring the adoption of theories able to predict size-effects. In this manuscript we demonstrate that the Cosserat medium is able to overcome these issues related to manufacturing processes simulation. We first provide a thermodynamically-consistent description of the Cosserat medium, and then we propose a method to calibrate the two additional characteristic lengths introduced by the Cosserat medium description by enriching the model with the TANH stress flow rule under adiabatic conditions.

在大多数金属制造过程中，介质会通过以相对较高的应变率产生大量塑性应变而变形，从而不可避免地引起温度升高。以低导热性为特征的金属可能会局部保留高温，因此会发生热软化。如果通过有限元方法将数值离散化，则控制连续体平衡的经典平衡定律将表现出严重的网格敏感性。此外，塑性变形趋于局限在特征长度与晶粒尺寸相当的狭窄区域中，从而需要采用能够预测尺寸效应的理论。在此手稿中，我们证明了Cosserat介质能够克服与制造过程仿真相关的这些问题。