Single crystal bulk material micro/nano indentation hardness testing by nanoindentation instrument and AFM

The micro/nano indentation hardness of single crystal aluminium and single crystal silicon are investigated. Load–depth curves can be obtained by nanoindentation instrument, and materials indentation hardness can be calculated by Oliver–Pharr method and work of indentation method directly from these curves. The hardness that obtained by Oliver–Pharr method is overestimate because of material pile-up effect, and the hardness that obtained by work of indentation method is not very correct because of its empirical equations inaccurate. The ‘true’ hardness can be calculated by plastic work of indentation and plastic volume that obtained by integrating fitted polynomial according to load–depth curves and atomic force microscopy, respectively. Comparison and analysis of the results that obtained by these methods are made.