How is titanium used to improve steel, aluminum, and copper alloys?

Titanium is a versatile alloying agent used to enhance the mechanical and structural properties of various metals, including steel, aluminum, and copper. Its specific contributions to these alloys include:1

• Steel: Titanium is used as a deoxidizer and as an alloying addition to reduce grain size, which strengthens the metal by restricting the flow of dislocations. In stainless steel, it is specifically used to reduce carbon content. Furthermore, titanium acts as a strong carbide or nitride former; these precipitates provide precipitation hardening and have a nucleation effect that slows crystal growth during cooling, further refining the grain size.21
• Aluminum: Titanium is added to aluminum alloys primarily to refine grain size, which improves the material's overall mechanical properties.1
• Copper: The addition of titanium to copper is utilized to produce hardening in the resulting alloy.1

In addition to these specific roles, small additions of titanium (typically less than 1 percent) are generally used in various metals to improve their formability and mechanical performance.3