Multi-Scale Modeling and Damage Analysis of Composite with Thermal Residual Stress

In order to analysis thermal residual stress and its influence on the strength of composite, the hierarchical multi scale simulation method is applied. A microscopic computational model of single fiber composite with thermal residual stress is built to research the stress distribution. Then the damage initiation discipline details of unidirectional composite are researched, and the effects of different fiber arrangements on thermal residual stress distribution, damage initiation and the different final failure behaviors of fiber regular distribution and random distribution under tension and compression are researched in details. It shows that in fiber regular arrangement, damage initiation in interface appears evenly and in matrix it appears at somewhere randomly. But in fiber random arrangement, initial damage focuses at the resin pockets between closely packed fibers with both interface and matrix damage. The maximal thermal residual stress in fiber random arrangement model is larger than that in fiber regular arrangement model. And it reaches the normal strength of the interface and thus causing the initiation of interface damage. Also the failure modes of composites under transverse tension and compression with and without residual stress are quite different from each other. The strength and failure path of different RVE and loading are showing respectively in this paper.