Processing maps have been built for > 30 years to predict the stable conditions for metal forming at high temperatures and strain rates. These maps, which also include efficiency conditions, are based on the stability criterion of Ziegler–Prasad (Z–P) within the framework of the dynamical materials model (DMM). In the present work, this criterion is drastically modified by introducing a Garofalo equation in the expression of the dissipative co-content, J, maintaining its definition in the framework of the DMM. This modification applies to its derivative with respect to the strain rate and also to the definition of efficiency, η. This new parameter developed in this work, named rho, ρ, is different from the stability parameter, xi, ξ, of the Z–P criterion since it is based on different constitutive equations. Rho is based on a Garofalo equation and xi on a power law equation. Both are obtained from experimental data and give rise to different stability maps that can be applied to any polycrystalline metallic material. In this work, a well-documented Ti-10V-4.5Fe alloy has been chosen to contrast the differences and similarities between the two methods of characterizing the stability conditions. Special emphasis is given to the predictions for the optimum forming temperatures.

已经建立了30多年的加工图，以预测高温和高应变速率下金属成形的稳定条件。这些图（其中还包括效率条件）基于动态材料模型（DMM）框架内的齐格勒-普拉萨德（Z-P）稳定性标准。在当前工作中，通过在耗散共含量J的表达式中引入Garofalo方程，并在DMM框架中保持其定义，对该准则进行了重大修改。此修改适用于其关于应变率的导数，也适用于效率η的定义。在这项工作中开发了这个新的参数，名为RHO，ρ，从稳定性参数，十一，不同ξ，因为它基于不同的本构方程。Rho基于Garofalo方程，xi基于幂律方程。两者均从实验数据获得，并产生了可应用于任何多晶金属材料的不同稳定性图。在这项工作中，选择了有据可查的Ti-10V-4.5Fe合金来对比两种表征稳定性条件的方法之间的异同。特别强调了最佳成形温度的预测。