Brass is the most widely used and least expensive of the copper-based alloys. They possess relatively good corrosion resistance, moderately high strength and, in some compositions, exceptionally good ductility and excellent forming characteristics when shaped by pressing, deep drawing, rolling, and machining. Improved tensile properties are the result of cold working. After cold working, they can be softened and recrystallized by appropriate annealing. The addition of lead to brass in amounts of 0.5 to 4% results in free-cutting of free-machining alloys in which elemental lead is present as uniformly dispersed particles. The high lead content results in relatively low ductility and plasticity.