Sensitivity of PMMA nanoindentation measurements to strain rate

ABSTRACT This study aims to investigate the effects of strain rate on polymethyl methacrylate (PMMA) nanoindentation measurements. Nanoindentation experiments were used to characterize the mechanical properties of PMMA. A wide range of strain rates were employed to examine strain rate sensitivity of PMMA. The test results indicate that the elastic modulus and hardness of PMMA are strain‐rate‐dependent. In addition, both the elastic modulus and hardness of PMMA exhibit increases with increasing strain rate. However, the elastic modulus became a stable value until strain‐rate of 0.2 s−1. Creep behavior of PMMA under the condition of high strain rate is more obvious than that experience a low strain rate. Moreover, the effects of strain rate on the PMMA nanomechanical properties are detailed analyzed by discussing each stage of the indentation process. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41896.