## 1 Introduction
### Foundry Alloys Al-Si  
Aluminum alloys are widely used in the foundry industry due to their favorable properties, such as low weight, good machinability, and castability. The die casting process is especially popular for producing complex-shaped and high-precision aluminum castings. This process involves injecting molten metal into a mold at high pressure, which results in a high-quality surface finish and dimensional accuracy of the final product. As demand for lightweight and high-performance components increases in various industries, including automotive, aerospace, and consumer electronics, die-cast aluminum alloys are expected to continue to grow [19; 20]. Al-Si alloys, also known as silumin, are widely used due to their favorable properties, including low specific weight, high corrosion resistance, and good castability. These alloys have a low tendency to shrink and crack, which makes them suitable for producing thin-walled castings with complex shapes. However, their machinability is slightly worse than other aluminum alloys due to the presence of hard and abrasive silicon particles [21; 22; 23]. The selection of the appropriate aluminum alloy for casting depends on both design and foundry properties. Design properties refer to the mechanical properties at standard, low, or high temperatures and the density-strength ratio, corrosion resistance, weldability, and machinability. These properties can be adjusted by selecting the appropriate alloy composition and heat treatment. On the other hand, foundry properties mainly relate to the casting process, including the running-in capacity, low tendency to shrink, low inclination to crack, and clink formation. The foundry properties can be optimized by adjusting the process parameters such as casting temperature, mold design, gating system, and cooling rate [24; 25]. The phase structure of Al-Si binary alloys is determined by the Al-Si equilibrium diagram (Figure 1). This diagram shows the phase relationships between aluminum and silicon as a function of temperature and composition. The Al-Si binary diagram is important in determining the processing conditions required to produce castings with the desired properties [3]. Aluminum has a relatively low melting temperature of around 660 \({}^{\circ}\)C, which makes it easily melted and cast into various shapes. Is lightweight with a specific gravity of  
Figure 1: Al-Si binary diagram. about 2.7 g/cm\({}^{3}\), making it ideal for applications where weight reduction is important. Aluminum exhibits excellent electrical conductivity, making it widely used in electrical wiring and components. It also has high thermal conductivity, making it useful in heat transfer applications, and is highly ductile, meaning it can be easily formed and shaped without breaking. This property makes it suitable for various forming processes like rolling, extrusion, and forging. While aluminum possesses good ductility, it generally has lower strength compared to other metals. However, the strength of aluminum can be enhanced through alloying and heat treatment processes. Silicon has a high melting temperature of approximately 1430 \({}^{\circ}\)C, making it suitable for applications that require materials with high temperature stability. Like aluminum, silicon has a low specific gravity, which contributes to its lightweight nature. Silicon is a brittle material, meaning it tends to fracture or break when subjected to stress or impact. Its brittleness makes it less suitable for applications requiring high toughness or impact resistance. Both aluminum and silicon have their unique properties and are widely used in various industries and applications [26; 27]. Aluminum and silicon form a binary eutectic alloy known as \(\alpha+\mathrm{Si}\). The eutectic point represents the composition and temperature at which the alloy has its lowest melting point and exhibits a specific microstructure.