ANALYSIS OF INDENTATION LOADING CURVES OBTAINED USING CONICAL INDENTERS

Using dimensional analysis and finite-element calculations we determin e the functional form of indentation loading curves for a rigid conica l indenter indenting into elastic-perfectly plastic solids. The new re sults are compared with the existing theories of indentation using con ical indenters, including the slip-line theory for rigid-plastic solid s, Sneddon's result for elastic solids, and Johnson's model for elasti c-perfectly plastic solids. In the limit of small ratio of yield stren gth (Y) to Young's modulus (E), both the new results and Johnson's mod el approach that predicted by slip-line theory for rigid-plastic solid s. In the limit of large Y/E, the new results agree with that for elas tic solids. For a wide range of Y/E, some difference is found between Johnson's model-and the present result. This study also demonstrates t he possibilities and limitations of using indentation loading curves t o extract fundamental mechanical properties of solids.