Alpha Beta Brass
|Alpha Beta Brass||
Brass containing over 36% of zinc or with other additions usually has two phases present in the crystal structure, alpha and beta. They are used for castings, extrusions and for hot stampings. A brass with sufficient zinc present to allow the development of the beta phase. The equilibrium range of the alpha-beta composition varies with temperature being 33.5 to 36.8% at the solidus temperature, and 35 to 46.6 % at room temperature. As the beta to alpha reaction is a diffusion controlled reaction, it is relatively slow, thus it is possible to control the relative proportion of alpha to beta phases by a combination of composition and heat treatment so that the combination of tensile strength to ductility can be optimised.