How does the addition of zinc to aluminum alloys affect their properties?

Adding zinc to aluminum alloys significantly enhances their mechanical properties, particularly strength and hardness. Zinc increases the alloy's resistance to deformation, making it more suitable for applications requiring high strength-to-weight ratios. This addition also improves the alloy's resistance to corrosion, especially in marine environments. However, it's important to note that excessive amounts of zinc can lead to a decrease in ductility and increase the risk of cracking, especially during welding or heat treatment processes. The addition of zinc also affects the alloy's thermal conductivity and electrical conductivity, typically reducing both. Overall, the addition of zinc to aluminum alloys is a balancing act to achieve desired properties for specific applications.