A practical guide for analysis of nanoindentation data

Mechanical properties of biological materials are increasingly explored via nanoindentation testing. This paper reviews the modes of deformation found during indentation: elastic, plastic, viscous and fracture. A scheme is provided for ascertaining which deformation modes are active during a particular indentation test based on the load–displacement trace. Two behavior maps for indentation are presented, one in the viscous–elastic–plastic space, concerning homogeneous deformation, and one in the plastic versus brittle space, concerning the transition to fracture behavior when the threshold for cracking is exceeded. Best-practice methods for characterizing materials are presented based on which deformation modes are active; the discussion includes both nanoindentation experimental test options and appropriate methods for analyzing the resulting data.