Most leaf springs are made of steel, but there are also a number of leaf springs on the market that are made from other metals, including aluminum and even titanium. The choice of metal for a leaf spring is typically dictated by the application for which it will be used. For example, lighter weight metals like aluminum may be used in applications where weight is a primary concern, such as in racing vehicles. Heavier duty metals like steel or titanium may be used in applications where strength and durability are more important, such as in off-road vehicles.