Advantages and differences between titanium and aluminium

Aluminum and titanium alloys, due to their excellent low density and structural strength, are used in a large number of applications in aerospace, automotive, and mechanical engineering, whether using 3D printing or CNC machining.

Although titanium is about two-thirds heavier than aluminum, its inherent strength means that less can be used to achieve the required strength. Titanium alloys are widely used in aircraft jet engines and all types of spacecraft, where their strength and low density reduce fuel costs. Aluminum alloy is only one-third the density of steel, and is the most widely used and common material for automotive lightweighting at this stage; there have been studies showing that aluminum alloys can be used for up to 540kg in a complete vehicle, in which case the car will lose 40% of its weight, and the all-aluminum bodies of vehicles from brands such as Audi and Toyota are good examples of this.
As both materials offer high strength and low density, other differentiating factors must be considered when deciding which alloy to use.

Strength/Weight: In critical situations, every gram of a part counts, but if a higher strength component is needed, titanium is the best choice. Because of this, titanium alloys are used in the manufacture of medical devices/implants, complex satellite components, fixtures and braces, and more.

Cost: Aluminium is the most cost-effective metal for machining or 3D printing; titanium costs more but can still drive a leap in value. The fuel savings for an aircraft or spacecraft from lighter parts will pay huge dividends, while titanium parts last longer.

Thermal properties: Aluminium alloys have high thermal conductivity and are often used to make radiators; for high-temperature applications, titanium's high melting point makes it even more suitable, and aero-engines contain a large number of titanium alloy components.