EFFECT OF COOLING RATE ON THE MECHANICAL PROPERTIES OF AA365 ALUMINUM ALLOY HEAT-TREATED UNDER T4, T5, AND T6 CONDITIONS

The mechanical properties of AA365, an Al-Si-Mn-Mg alloy used in high-pressure die-casting of automotive parts, can be optimized for a proper application using different heat treatments. During a die-casting process including heat treatment, aluminum alloy cast components experience considerable changes in their mechanical properties due to the non-uniform cooling phenomena. The mechanical properties of AA365 with different cooling rates during T4, T5, and T6 heat treatments were investigated and analyzed by a statistical method using a design of experiments protocol to see which factor is most significant for mechanical properties. The factors used in this study are the type of heat treatment and cooling rate of each step. The microstructural analysis was conducted to observe the mechanism of mechanical property changes. The combination of heat treatment type and cooling rate enabled the control of ductility and strength properties in AA365.