Nanoindentation characteristics on polycarbonate polymer film

The nanoindentation experiment was carried out to estimate nanomechanical characteristics of polycarbonate polymer films. Hardness, effective elastic modulus and contact stress-strain rate curve were obtained. The results showed that the effective elastic modulus and the hardness decreased as the applied load was increased. As the hold time was increased, the effective elastic modulus and the hardness also decreased. Furthermore, decreasing the loading rate also decreased the effective elastic modulus and the hardness. A power-law creep equation was obtained. When taking a log coordinate to the equation, the contact stress increased as the contact strain rate increased and has a linear appearance. (C) 2004 Published by Elsevier Ltd.