A procedure for predicting strength properties using small punch test and finite element simulation

Abstract

Developing a universal approach for acquiring yield strength and ultimate tensile strength by small punch test (SPT) is a long-standing challenge. In this paper, a methodology is proposed to obtain strength properties of bulk materials from SPT results. It involves extracting true stress–strain curves from SPT data using iterative finite element simulation. Acquired curves show that initial yield stress cannot be reproduced. This is attributed to the inhomogeneous deformation of SPT specimens. Finite element simulations were then conducted on tensile tests with the extracted true stress–strain curves to obtain strength. Results indicate that predicted strength shows a convergent tendency with the times of iterative finite element simulation. An approach is proposed to process the predicted strength, based on data analysis. The acquired strength properties are in good agreement with those obtained by standard tensile testing. This is an entirely novel procedure that predicts reliable tensile properties via a single SPT run. It can be employed with confidence to cases for which standard tensile testing is impractical.