Nanoscale mechanical characterization of polymers by atomic force microscopy (AFM) nanoindentations: viscoelastic characterization of a model material

摘要: The atomic force microscope (AFM), apart from its conventional use as a microscope, is also used for the characterization of local mechanical properties polymers. In fact, elastic purely materials using this instrument can be considered well-assessed technique while viscoelastic remains challenge. particular, one finds behavior changing when performing indentations at different loading rates, i.e. on time scales. Moreover, apparent due to complex contact mechanics phenomena, with onset plasticity and long-term features which cannot identified by curve alone. For reason, characterization, thus study effects indentation rate temperature, was done model where such additional phenomena are not observed. Another dependence originating itself has been decoupled. found reproducible even if changes experimental set-up far preliminary determinations concerning AFM nanoindentations well performed. temperature scales have undertaken. A check time–temperature superposition attempted through WLF equation activation energies elementary motions in rubbery glass transition regions good agreement expected values.