Determination of crack-free mechanical properties of brittle materials via single nanoindentation

Due to cracking, mechanical properties of brittle materials (without interruption of cracking) have not been obtained by experiments. A novel method of using single nanoindentation is developed to determine crack-free mechanical properties (elastic modulus, zero pressure yield strength, and friction angle in a linear Drucker-Prager model) of brittle materials with pressure-dependent yield behavior. Nanoindentation experiments on glass, rock, and ceramic materials were conducted, and then a finite element model is established by applying the linear Drucker-Prager model. The sensitivity of measured properties on the (input) experimental data is discussed. Based on experimental data and numerical analysis of indentation response, crack-free mechanical properties are determined. The validity of determined mechanical properties is confirmed by comparing values with those obtained in previous studies. We expect that the proposed method would contribute to describing pressure-dependent plastic behavior of brittle materials. (C) 2020 Elsevier Ltd. All rights reserved.