Influence of sample thickness and experimental device configuration on the spherical indentation of AISI 1095 steel

Most instrumented indentation theoretical studies and models consider bulk sample geometry, which implies no influence on the indentation response. In the particular case of thin samples, our previous studies have shown that the thickness has an influence on the experimental device behavior as well as on the sample and material response. This work is a numerical and experimental illustration of this particularity. Spherical macroindentation tests are performed on AISI 1095 steel samples of thicknesses varying from 0.55 to 10 mm. Experimental and numerical results are compared. Experimental limitations are investigated, and solutions to obtain results that are independent of the sample thickness and curvature are proposed. We show that the proposed solution leads to a reliable identification of the material mechanical properties of thin and moderately bent samples.