A load-based depth-sensing micro-indentation technique has been developed for material mechanical properties evaluation including elastic modulus, yield stress, strain hardening exponent and stress-strain curve. Based on a Hertzian contact mechanics approach, this load-based depth-sensing micro-indentation technique does not require system compliance calibration or the use of high precision depth sensors. Furthermore a unique, material independent, indentation based load-depth algorithm has been developed accounting for both elastic and elastic-plastic deformation of the material beneath the indenter. This algorithm, found to be a function of material yield stress, strain hardening exponent and elastic modulus, is shown to be the basis for obtaining a stress-strain curve. Finite element analyses of multiple materials with various mechanical properties were employed to examine and develop the fundamental indention based relationships between these variables and the load/depth curve needed to extract the stress-strain diagram. In addition, experimental results obtained with this load-based micro-indentation technique were found to yield accurate material mechanical properties (elastic modulus, strain hardening, yield strength) at room and elevated temperatures (up to 1200°C).
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