Experimental and modeling investigation on compression springback property of mullite fiber reinforced silica aerogel composites

Uniaxial compression tests were carried out on mullite fiber reinforced silica aerogel composites in the out-of-plane direction. Influences of different ultimate strains and thermal exposure temperatures on the compression springback behavior and deformation recovery capability were investigated. Internal mechanisms based on the microstructure morphology changes were explained. Phenomenological mechanical models were established respectively for the deformation behavior in the loading and unloading stages. The results show that the compression springback behavior of mullite fiber reinforced silica aerogel composites exhibits nonlinear characteristics. The greater the ultimate strain, the worse the deformation recovery capability. High temperature thermal exposure pre-treatment has an effect on the compression springback property, the higher the thermal exposure temperature, the worse the deformation recovery capability. The aggregation of matrix particle-cluster structure and the formation and collapse of the large size holes are main causes. The phenomenological mechanical model can be used to describe the stress-strain curve of the composites during loading and unloading. The fitting results are in good agreement with the experimental data