Toward an Instrumented Strength Microprobe – Origins of the Oliver-Pharr Method and Continued Advancements in Nanoindentation: Part 2

Abstract

Numerable advancements have afforded many benefits to nanoindenter system operators since the late 20th century, such as automation of measurements, enhanced load and displacement resolutions, and indentation with in-situ capabilities. Accordingly, the present chapter details how the Oliver-Pharr method of nanoindentation testing and analysis was adopted and relied upon as a framework that brought about widespread advancements in instrumented indentation testing. The present chapter introduces an emergent and theoretically consistent approach to assessing true stress–strain curves at a micromechanical scale using a flat-punch nanoindenter tip geometry and reliance upon Hollomon power-law plasticity and constitutive parameter fitting. Finally, a novel flat-punch nanoindentation testing method and approach to plasticity parameter analysis for metallic materials using nanoindentation systems can be implemented, bringing about an instrumented strength microprobe – a long sought-after tool.