The measurements of nanomechanics have been established to study the effects of strain burst and pile-up on the hardness and elastic modulus of single crystal copper samples. For nanoindentation of the single crystal copper subjected to various loadings, the residual depths have been analyzed and compared with the cross sectional depth profile obtained by the atomic force microscope (AFM). A penetration depth around 5 to 8 nm is observed before the strain burst. It is found that the critical load to cause the first burst slightly decreases with increasing loading rate. A new graphical method based on the 3-D image of indent was proposed to eliminate the hardness and elastic modulus errors induced by the pile-up effect. The hardness and elastic modulus are not influenced by the value of maximum load and reduced to around 95% of their direct measurement values based on the Oliver-Pharr method. In comparison, the hardness decreases with increasing maximum load and shows strong dependence with the maximum load applied when the work of indentation method was employed.

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