Determining suitable parameters for inverse estimation of plastic properties based on indentation marks

Abstract

Tensile elastoplastic properties are extensively used in engineering applications; however, sample preparation for tensile tests is time-consuming. Therefore, a technique to estimate the tensile properties from an indentation test, with relatively easy sample preparation, is useful to reduce effort and accelerate the evaluation of advanced materials. Previously proposed techniques for the inverse estimation of elastoplastic properties used plural load-displacement curves. In this study, the authors proposed an estimation technique based on a single indentation involved using three-dimensional information of an indentation mark in addition to a load-displacement curve. To determine the parameter suitable for use in the inverse estimation of elastoplastic properties, the sensitivity and experimental variation in parameters extracted from the indentation results were investigated. The maximum pile-up height normalized by the maximum indentation depth, Zmax/hmax, was determined as the suitable parameter for inverse estimation owing to its high sensitivity compared to experimental variations. Moreover, the stress-strain curve obtained using this technique agreed with that obtained using dual indenters.