Metals identification from instrumented spherical indentation testing

A new integrated system consisting of a testing machine, denominated Diaptometro, and of an algorithm for metallic materials identification via instrumented spherical indentation testing is presented. The experimental load L– penetration depth ℎ curve (L − ℎ curve) are collected from shallow indentation tests, thus preventing friction effects in the material properties estimation, and used in a inverse analysis based on the numerical simulation of the indentation process for a wide range of metallic materials. Accuracy in the experimental data acquisition and in the L − ℎ curve representation were recognized to be the key factors for reliable and accurate estimations. A new experimental equipment was specifically built-up, whereas a four-terms power expansion showed to be very effective for modeling the L − ℎ curve. Experimental validation campaigns confirm the effectiveness of the adopted solutions.