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The effect of alloying elements on thermal stability of five different near eutectic Al-Ce based alloys, i.e., Al-12Ce, Al-12Ce-4Si, Al-12Ce-0.4Mg, Al-12Ce-4Si-0.4Mg and Al-12Ce-4Si-0.4Mg-0.25Sr alloys were investigated. The alloys were heat treated at three different temperatures, i.e., 200 °C, 300 °C and 400 °C to establish the thermal stability. Binary Al-12Ce alloy consisting of α-Al and showed higher resistance to coarsening at all temperatures. Addition of Si decreases the thermal stability above 200 °C while combined addition of Si and Mg increases the thermal stability up to 300 °C. Addition of Sr to quaternary alloy was not beneficial to enhance the thermal stability.

The strength of aluminum alloy decreases sharply with the increase of temperature. One of the major drawbacks of aluminum alloys is that it does not retain their mechanical properties at higher temperatures. To solve this problem, the high-temperature stability of the Al-Ce system is studied. The effect of alloying elements on the thermal stability of five different near eutectic Al-Ce based alloys, i.e., Al-12Ce, Al-12Ce-4Si, Al-12Ce-0.4Mg, Al-12Ce-4Si-0.4Mg and Al-12Ce-4Si-0.4Mg-0.25Sr alloys, were investigated. The alloys were heat treated at three different temperatures, i.e., 200 °C, 300 °C and 400 °C, to establish thermal stability. Binary Al-12Ce alloy consisting of α-Al and showed higher resistance to coarsening at all temperatures. The addition of Si helps retain the microstructure stability above 200 °C and the combined addition of Si and Mg increases the room and high-temperature strength up to 300 °C. The addition of Sr to quaternary alloy was not beneficial for enhancing thermal stability.

Owing to manufacturing challenges, the fabrication of thin sheets of metal matrix composites has been an area of concern for sheet manufacturers. Converting a billet of composite into a sheet using rolling and extrusion is quite energy-intensive and prone to cracking using the conventional casting route. To address this issue, the present study explores the development of particle-reinforced near eutectic Al-Mg2Si composite sheets using a vertical twin-roll continuous casting process. The numerical simulation involves fluid flow, solidification, and heat transfer analysis of the twin-roll continuous casting process for producing thin strips. Processing parameters such as the velocity of rolls and superheat temperature of the melt are optimized to successfully convert the melt into a sheet of composite material. A combined numerical and experimental study shows that the CC process is more sensitive to the casting speed. A small change in roller speed (2 rpm) significantly affects the solidified fraction at the roller exit. Optimizing the casting speed to 0.072 m/s and inlet temperature to 886 K, an in-situ Al-Mg2Si composite sheet of 3 mm thickness is successfully cast. The particle distribution along the casting direction of the sheet is uniform, ensuring the homogeneous mechanical properties reported in terms of hardness. The entire process does not require external stirring to get uniform distribution of the reinforced particles.

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