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
Heated glass surface of the glass between the busbars must be flat. An electric current flows across the tin(II) oxide coating from one busbar to the other. The electrical resistance of the coating produces heat energy, which radiates from the glass. The busbars are connected to a power control unit that regulates the flow of electricity and thus the temperature of the glass. In modern architectural projects the heated glass is completely translucent. This technology uses a special metallic coating on the surface of the glass invisible to the naked human eye. A pane of heated glass can achieve temperatures up to