硅粉填充改性GFRP的力学性能及其增强机理OA

This study employs the vacuum-assisted resin transfer molding(VARTM)process to modify glass fiber reinforced polymer(GFRP)using micron-sized silica powder.The influence of silica powder content on the flexural strength,short beam shear strength,and in-plane shear strength of the V-notched beam of GFRP was examined.The enhancement and thermal resistance mechanisms of the modified fiber composites are elucidated through scanning electron microscopy(SEM)and dynamic thermomechanical analyzer(DMA).The results show that at a silica power content of 1%,the flexural strength,short beam shear strength,and in-plane shear strength of the composite increase by 22%,23%and 17.4%,respectively,compared to the unmodified material,while the glass transition temperature(Tg)rises by 3.8℃.At this optimal silica content,the silica particles are well-distributed in the resin matrix and exhibit good adhesion to the glass fibers,facilitating a mechanical interlocking effect that enhances material strength.Additionally,uniformly dispersed inorganic particles promote crack deflection,delay crack propagation,and inhibit the formation of macro-cracks,thus improving the toughness of the composite.However,further increasing the silica power leads to particle agglomeration,which diminished the inerfacial bonding between the fibers and the resin,resulting in a decrease in composite strength.Moreover,the introduction of inorganic particles enhances the crosslinking density of epoxy resin chains,improving the heat capacity and thermal conductivity of the resin system,consequently enhancing the heat resistance of the composite materials.