Impression deformation of carbon-microsphere and polytetrafluoroethylene composite

Carbon-based materials have been extensively used in the devices and systems for energy storage, catalysis, etc. The mechanical behavior of the carbon-based materials plays an important role in the performance and reliability of the devices and systems. In this work, we use impression test to investigate the deformation behavior of carbon-microsphere and polytetrafluoroethylene composite, in which the carbon microspheres are fabricated from high-fructose corn syrup via hydrothermal process. The three-parameter Weibull model is used to analyze the contact modulus, maximum impression depth and energy dissipation per impression cycle. The impression modulus, maximum impression depth and dissipated energy increase with the increase of the impression load and holding time, which are due to impression-induced consolidation of the carbon-sphere-based composite. A simple relation between the Young's modulus of the carbon-microsphere-based composite and the ratio of the maximum impression depth to the sample thickness is developed and supported by the experimental results.