This manuscript presents a multi-yield surface model to idealize the mechanical behavior of viscoplastic solids subjected to cyclic loading. The multi-yield surface model incorporates the evolution of nonlinear viscoplastic flow through a piece-wise linear hardening approximation. A kinematic hardening law is employed to account for the evolution of backstress with respect to the viscoplastic strain rate. The new backstress evolution strategy is proposed to ensure that all yield surfaces remain consistent (i.e., satisfying collinearity) throughout the viscoplastic process. The multi-yield surface model is coupled with viscoelasticity to approximate the relaxation behavior of high temperature metal alloys. The model is implemented using a mixed finite element approach. The capabilities of the proposed approach are demonstrated using experiments conducted on a high temperature titanium alloy (Ti-6242S) subjected to static, cyclic and relaxation conditions.

中文翻译：

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粘塑性材料的多屈服表面建模

这份手稿提出了一个多屈服表面模型，以理想化粘塑性固体在循环载荷下的力学行为。多屈服表面模型通过分段线性硬化近似结合非线性粘塑性流动的演变。采用运动学硬化定律来解释背应力相对于粘塑性应变率的演变。提出了新的背应力演化策略以确保所有屈服面在整个粘塑性过程中保持一致（即满足共线性）。多屈服表面模型与粘弹性耦合以近似高温金属合金的松弛行为。该模型是使用混合有限元方法实现的。