Predication of A Mathematical Model for A Hardness in Steel-52100

Abstract

This paper reports research in which an attempt was made to predict a mathematical model of hardness for steel-52100. The primary objective was to investigate the effect of heat treatment parameters on the hardness of steel-52100, where the value of hardness is influenced by these parameters (Austenitizing temperature, tempering temperature, and tempering time). To determine the influence of these parameters, experiments were conducted using Taguchi's orthogonal array. The results of these experiments were used to plot the response graph, and Pareto diagram and to calculate S/N ratios. An empirical model for the hardness in terms of the parameters mentioned was also developed. Coefficient of determination was used to check the adequacy and accuracy of the model. The empirical model so developed was checked by conducting confirmation experiments. Contour plots were plotted to visualize the effect of those heat treatment parameters on the hardness. Those parameters were optimized to maximize the hardness using the larger-the-better concept of robust design and also compared with the optimized parameters obtained using the developed empirical model. Finally, this study shows a good agreement between the mathematical model and experimental results.