Abstract In this contribution, a probabilistic micromechanics damage framework is presented to predict the macroscopic stress–strain response and progressive damage in unidirectional glass-reinforced thermoplastic polymer composites. Motivated by different failure modes observed experimentally, the damage mechanism in the vicinity of the fibers (namely, the interphase) is characterized by initiating and growing voids. The mechanisms can be formulated through a Weibull probabilistic density function. In contrast, the ductile progressive degradation of matrix initial stiffness is analyzed via the continuum damage theory. To accommodate different damage mechanisms in the matrix and the interphase, a three-phase Mori-Tanaka (MT) method and transformation field analysis approach (TFA) are established within a unified framework that allows simulation of both ductile and discrete damages in different phases. Moreover, the rate-dependent viscoelastic and viscoplastic response of the polymer matrix phase is modelled through a phenomenological model consisting of four Kelvin-Voigt branches and a viscoplastic branch under the thermodynamics framework. The reliability and efficiency of the modified mean-field damage model, based on TFA and Mori-Tanaka scheme, are assessed by comparing the simulated stress-strain response against full-field Abaqus simulations under both unidirectional and multiaxial nonproportional loading paths at different loading rates. The developed model provides an efficient alternative to the finite-element based full-field homogenization schemes or other mean-field micromechanics techniques that may be compared, as well as a framework for a potential extension of the theory for simulating damage evolution in composites with random reinforcement orientations.

中文翻译：

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界面脱粘和基体延性损伤引起的混合渐进退化的粘弹性-粘塑性聚合物复合材料的扩展平均场均质化

摘要 在这篇文章中，提出了一种概率微观力学损伤框架来预测单向玻璃纤维增​​强热塑性聚合物复合材料的宏观应力应变响应和渐进损伤。受实验观察到的不同失效模式的驱动，纤维附近（即界面）的损伤机制的特征在于起始和增长的空隙。这些机制可以通过威布尔概率密度函数来表述。相比之下，基体初始刚度的延性渐进退化是通过连续损伤理论分析的。为了适应基质和界面中不同的损伤机制，三相 Mori-Tanaka (MT) 方法和转换场分析方法 (TFA) 在统一框架内建立，允许模拟不同阶段的延性和离散损伤。此外，聚合物基体相的速率相关粘弹性和粘塑性响应通过由四个 Kelvin-Voigt 分支和热力学框架下的粘塑性分支组成的现象学模型进行建模。通过比较模拟应力应变响应与全场 Abaqus 模拟在不同加载速率下的单向和多轴非比例加载路径下，基于 TFA 和 Mori-Tanaka 方案的修正平均场损伤模型的可靠性和效率.