1.1 ,This specification covers a variety of ferrous PM structural materials and includes a classification system or material designation code. The classification system used in this specification includes chemical composition, minimum tensile, 0.2 ,% offset yield strength for as-sintered materials, and minimum ultimate tensile strength for heat-treated materials (sinter hardened or quenched and tempered). It also contains minimum density and maximum coercive field strength requirements for iron-phosphorus materials.