Detailed observations of nanoindentation static creep effects exhibited in polymethylmethacrylate (PMMA) is presented and discussed in this study. One-indent nanoindentation technique, the partial unloading measurement (PUM) method, is compared with the basic measurement BM method (i.e., an array of multiple single indents with various magnitudes). The experimental results for PMMA reveal a strong dependence on the loading conditions. It was found that the PUM results for PMMA are not consistent with the corresponding BM results due to significant static. The creep depths accumulated and increased the indentation depth, and thus the contact area. The hardness and elastic modulus evaluated from these experimental results decreased with the indentation depth (or load).
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