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It is well known that pure aluminium exhibit poor tensile properties besides having qualities like good corrosion resistance, light weight, ductility, good fluidity etc. Therefore alloy of aluminium is preferred over pure aluminium. Alloy of aluminium with metals like copper, magnesium, silicon as major alloying elements improve its tensile behaviour and make it more useful for different applications. Aluminium alloy is gaining popularity within automotive and aviation industries in recent years due to many reasons. High strength to weight ratio, ease in choice of different manufacturing processes, nontoxic behaviour, corrosion resistance are few to be named. Alloy of aluminium with Cu and Mg can retain good mechanical properties even under high temperature applications. Most of the aluminium alloy response to heat treatment are also excellent. (Cole and Sherman,1995;Ye,2003;Hirsch,1997;Huda et al,2009)It is well established that 2xx.x series of aluminium alloy capable of giving cast components showing highest strength among all cast alloys. Good foundry techniques and designs should be implemented to get the best mechanical properties deliverable by this series of alloys (Davis, 2001). Most of the materials which exhibit excellent properties during ambient temperature applications may not behave the same during high temperature operations. For these alloy surface coating is applied for withstanding high temperature. (Vasudev et al,2020; Rukhande et al,2021; Praveen & Arjunan, 2022). Many authors have established that addition of copper with aluminium can impact high temperature operational conditions when compared to any other major alloying element . Adding copper to commercially pure aluminium transform the columnar structure to equi-axial grains and it also result in a linear increase of the micro hardness. Copper is used as alloying element where strength is required at room and at elevated temperature. (Kaufman &Rooy,2004) Research suggest that increasing copper content beyond maximum solid solubility limit in aluminium increase the precipitation hardening effect and consequently strength at elevated temperature. Increasing the copper content decreases the elongation. (Bozorgi &Andres,2018)
In case of cast aluminium alloys its mechanical properties are dependent on the microstructure developed during the solidification. The microstructure developed is dependent on many factors. Some of them are composition of alloy, cooling rate, casting process, heat treatment. Other factor that determine the mechanical properties of the alloy are defects developed during solidification. (Rana et al, 2012; Vasconselos et al, 2016; Talamantes-silva et al,2008] Study show that decrease in DAS (dendrite arm spacing) of α-Aluminium phase achieved due to fast cooling rate increases the strength and hardness of Aluminium alloy. (Lee &Mishra,2017)