Heat Treatment Optimization of CA-6NM Cast Alloy Using a Full Factorial Design of Experiments Approach

A full factorial experimental design was used to study the effect of each parameter involved in the heat treatment of the CA-6NM cast alloy, in order to optimize this process for achieving specific hardness values after single or double tempering-processes. The statistical analysis of the experimental results with ANOVA showed that the chemical composition, the equivalent Cre/Nieratio and the carbon content are critical parameters that should be considered for the determination of AC1temperature. For a single tempering process, a decrement from 30HRC to 25HRC was reached as the austenitizing and tempering temperatures were increased or with prolonged austenitizing times. In order to achieve specific hardness values