Abstract: An atomic force microscopic study was performed to determine elastic modulus of single secondary particle on silica aerogel monolith. Based on the distance-applied load curves of single crystal silicon wafer, the cantilever deformation at the initial contact point of the tip on the particle sample could be determined. By substituting the secondary particle for the silicon wafer, the depth-applied load curves were obtained by analyzing the corresponding distance-applied load curves. The elastic modulus is calculated to be 5.6 GPa for the highly porous silica aerogel by fitting the elastic part of depth-applied load curve with the Hertzian equation, which shows ten times smaller than that of the fused silica (72.5 GPa) due mainly to the agglomerated structure formed by the primary particles.
Authors: Xiaoyong He, Xuan Cheng, and Ying Zhang
Keywords: Atomic Force Microscopy, Silica Aerogel, Elastic Modulus, Secondary Particle