【摘要】 基于短纤维增强金属基复合材料(MMC)的单纤维三维模型(三相),利用粘弹性有限元分析方法对影响金属基复合材料的蠕变行为的因素进行了较为系统的分析。研究中主要讨论了界面特性和纤维取向角对金属基复合材料的蠕变性能的影响。研究结果发现,界面特性诸如厚度、模量和应力指数都对纤维最大轴应力和稳定蠕变率产生影响:稳态蠕变率随界面模量的增大而逐渐减小,当高于基体模量时基本保持不变;纤维轴应力的变化与蠕变率正好相反。稳态蠕变率随界面厚度、应力指数的增加而增大;而轴应力则随之减小。同时不同的纤维取向也影响金属基复合材料蠕变时的轴应力分布和稳态蠕变率。更多还原

【Abstract】 Based on the 3D unit cell model of short fiber enforced metal matrix composites, finite element method (FEM) is applied to analyze the influence on the creep behavior. Special attention is put on the influence of the interphase properties and the direction of fiber axial direction to the loading direction. The study shows that the interphase properties such as thickness, elastic and creep material properties have influence on the axial stress states and steady creep rates of the composites: the steady creep rate increases as thickness and stress exponent increasing; but the axial stress minimizing. However, a certain level occurs, when the interface modulus higher, the creep rate and axial stress don’t change. The loading direction relating to the fiber axial direction has also influences.更多还原