Annealing (metallurgy) brass can be cooled slowly in air, or quickly by quenching in water, unlike ferrous metals, such as steel, which must be cooled slowly to anneal. In this fashion, the metal is softened and prepared for further work—such as shaping, stamping, or forming. Annealing occurs by the diffusion of atoms within a solid material, so that the material progresses towards its equilibrium state. Heat increases the rate of diffusion by providing the energy needed to break bonds. The movement of atoms has the effect of redistributing and eradicating the dislocations in metals and (to a lesser extent) in ceramics. This
Bioabsorbable metallic glass Bioabsorbable metallic glass Bioresorbable (or bioabsorbable) metallic glass is a type of amorphous metal, which is based on the "Mg-Zn-Ca ternary system". Containing only elements which already exist inside the human body, namely Mg, Zn and Ca, these amorphous alloys are a special type of biodegradable metal. The first reported metallic glass was an alloy (AuSi) produced at Caltech by W. Klement (Jr.), Willens and Duwez in 1960. This and other early glass-forming alloys had to be cooled extremely rapidly (in the order of one mega-kelvin per second, 10 K/s) to avoid crystallization. An important consequence of this was that