P-h Curves and Hardness Value Prediction for Spherical Indentation Based on the Representative Stress Approach

In this work, finite element (FE) model of spherical indentation has been developed and validated. The relationships between constitutive materials parameters (sy and n) of elastic-plastic materials, indentation P-h curves and hardness on spherical indenters has been systematically investigated by combining representative stress analysis and FE modelling using steel as a typical model material group. Parametric FE models of spherical indentation have been developed. Two new approaches to characterise the P-h curves of spherical indentation have been developed and evaluated. Both approaches were proven to be adequate and effective in predicting indentation P-h curves. The concept and methodology developed is to be used to predict Rockwell hardness value of materials through direct analysis and validated with experimental data on selected sample of steels. The Hardness predicted are compared with the experimental data and showed a good agreement. The approaches established was successfully used to produce hardness values of a wide range of material properties, which is then used to establish the relationship between the hardness values with representative stress.