基于并行耦合多尺度建模的混杂增强铝基复合材料切削亚表面损伤机理研究

混杂增强铝基复合材料的切削亚表面损伤是制约其结构件可靠性应用的关键瓶颈之一。现有的基于微-宏观的多尺度方法由于忽略刀具-增强相的交互作用及各尺度间的耦合，无法对切削亚表面的局部微观变量实现准确预测及分析。本项目拟以颗粒/晶须混杂增强铝基复合材料为研究对象，考虑材料微尺度结构特征(界面和微空洞)的影响，引入混杂增强相嵌入式的细观代表性体积元建模方法，实现刀具-混杂增强相交互作用的表征及分析；通过研究各个尺度的耦合机理及损伤传递准则，建立微-细-宏观并行耦合的多尺度有限元模型，系统探索亚表面层颗粒、晶须、界面、晶须周围颗粒四种位置处的微观应力场、应变场、温度场的变化规律及差异特性，揭示混杂增强铝基复合材料的协同交互机制及其影响下的混杂增强相变形机理和亚表面损伤形成机理。项目的研究对该类材料在我国航空、航天、汽车等重要领域的可靠性应用提供理论指导。

The subsurface damage in machining hybrid reinforced aluminium matrix composites is one of the key bottlenecks for the reliability application of its machining structures. Due to ignoring the interaction of the tool with reinforcement and the coupling analysis between scales, the existing multi-scale modeling method based on micro-mesoscale cannot provide accurate prediction and analysis of local microscopic variables within sub-surface. This project intends to take the particle/whisker hybrid reinforced aluminium matrix composites as the research target. While considering the influence of the materials microscale structure (interface and micro voids), mesoscale representative volume element modeling method is introduced to realize the interaction representation of the tool with hybrid reinforcements. A micro-meso-macro scale concurrent coupled multi-scale model is thus established through studying the coupling mechanism and damage transition criterion. Based on the aforementioned method, the change regulation and difference of microscopic stress field, strain field and temperature field around the four kinds of location as well as the particles, whiskers, interface, and particles around the whiskers are investigated systematically. Finally, the deformation mechanism of hybrid reinforcement and subsurface damage mechanism influenced by the cooperative interaction of hybrid reinforced aluminium matrix composites will be revealed. The research provides theoretical guidance for the development and application in the paramount field of the national economy, e.g. aviation, aerospace, automobile.