Deformation Behavior of Glass Fiber Reinforced AerogelUnder Dynamic Compression

Dynamic compression test on glass fiber reinforced aerogel has been done by Hopkinson pressure bar. Method of accurately controlled strain was used to freeze different stages of compression process. Failure process of glass fiber reinforced aerogel has been studied by microanalysis and porosity analysis of aerogel under different strain. The results showed that under dynamic compression, the nano-porous network structure of aerogel is destroyed, the glass fibers break down gradually, the pores shrink and even result in pore collapse, the connectivity of pores becomes worse, colloidal particles are squeezed closer to one another. Under dynamic compression condition, the critical failure strain of aerogel is about 0.80. The mechanical behavior of aerogel displays a marked strain rate strengthening effect. Under dynamic compression, the failure is due to the increase of lateral tensile stress of pore wall and high speed collision between colloidal particles.