Adding different amounts of titanium to an aluminum-copper alloy can significantly affect its strength, hardness, and overall properties, making it more or less suitable for aerospace applications.1. Strength: Titanium is known for its high strength-to-weight ratio, which means that adding it to an aluminum-copper alloy can increase the overall strength of the material. As the percentage of titanium increases, the strength of the alloy generally increases as well. This is because titanium forms intermetallic compounds with aluminum and copper, which can act as reinforcing agents within the alloy.2. Hardness: The hardness of the alloy can also be affected by the addition of titanium. The formation of intermetallic compounds can increase the hardness of the material, making it more resistant to wear and deformation. However, excessive amounts of titanium can lead to the formation of large, brittle intermetallic phases, which can decrease the overall toughness and ductility of the alloy.3. Aerospace applications: For aerospace applications, materials need to have a combination of high strength, low weight, and good corrosion resistance. Adding titanium to an aluminum-copper alloy can improve these properties, making the material more suitable for use in aerospace components. However, it is essential to find the optimal amount of titanium to add, as too much can lead to a decrease in ductility and toughness, which can be detrimental to the material's performance under the demanding conditions of aerospace applications.In conclusion, adding different amounts of titanium to an aluminum-copper alloy can have a significant impact on its strength, hardness, and overall properties. The optimal amount of titanium should be determined through experimentation and analysis to ensure that the alloy has the desired combination of properties for aerospace applications. This can involve testing various compositions for their mechanical properties, corrosion resistance, and performance under extreme conditions, such as high temperatures and pressures.