Abstract
The Al-Fe-Ni-Mg-Si system has demonstrated castability, electrical and thermal conductivity, and mechanical properties suitable for modern electrical and hybrid vehicle components. The low solubility of Fe and Ni in solid state Al (0.052 wt.% and 0.04 wt.%, respectively) result in the formation of intermetallic phases that improve strength and maintain electrical and thermal conductivity. Additional improvements can be seen with the addition of Mg and Si alloying elements due their ability to dissolve into the Al matrix and form intermetallic phases. The presence of the intermetallic phases and the relatively high solubility of Mg and Si (17.4 wt.% and 1.65 wt.%, respectively) suggest that the Al-Fe-Ni-Mg-Si system is susceptible to heat treatment to further modify properties. Three alloy compositions were solutionized (530-620 °C for 2-8 hours), aged (150-300 °C for 1-4 hours), or solutionized (530-620 °C for 2-8 hours) and aged (150-300 °C for 4 hours) for analysis. Microhardness and electrical conductivity measurements were collected prior to and after each heat treatment procedure. Statistical analysis was then used to determine the change in properties due to each treatment. Tensile samples underwent select heat treatment procedures to determine their effectiveness on the strength and other mechanical properties of each alloy. The heat treatability of the alloying system has demonstrated its adaptability, electrical conductivity (42-52 IACS%), and hardness (55-75 HV).