This is an example of a metal matrix composite. Fine silicon carbide particles are added to a conventional Al-Cu or Al-Zn matrix to improve the stiffness, strength, wear resistance and creep resistance. The lower density of SiC compared to aluminium also reduces the density of the composite. The toughness, ductility and fatigue resistance may, however, deteroriate.
Typical applications for metal matrix composites include engine pistons, cycle frames, brake pads and even racing shoes for horses!