Multi-Response Optimization of Heat Treatment Parameters for Al-Fe Alloy Mixed Aluminum Beverage Cans

This research investigates the effect of heat treatment parameters on the hardness and corrosion resistance of hypereutectic Al-Fe alloy mixed with 75% aluminum cans. Alloying elements like Mg, Si, and Cu have the potential to enhance hardness through heat treatment. In this study, a 24-full factorial design was employed, with 4 factors: solution heat treatment temperature, solution heat treatment time, aging temperature, and aging time. Analysis of variance results indicates that the solution heat treatment temperature and time have no significant effect on response variables, while the aging temperature and time significantly influenced all response variables. The optimal parameters identified are aging temperature at 150 ºC and aging time at 8 hours, achieving the desired response variables. Factors with insignificant effects on the solution heat treatment may be due to the amount of alloying elements that have dissolved completely in the aluminum matrix at temperatures lower than the study's limit. Furthermore, the significant factor affecting all response variables is the aging process, which is related to the precipitation of the secondary Mg2Si phase. This precipitation hardening contributes to enhancing the hardness but if this phase is oversized, it may lead to the loss of corrosion resistance properties of the aluminum alloy.
Keywords: Analysis of variance, Heat treatment, Precipitation, Hardness, Corrosion resistance