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
Glass-to-metal seal will not go through the wall of the container but it will reach the surface on the same side where it started and the seal will not leak despite the crack. Another important aspect is the wetting of the metal by the glass. If the thermal expansion of the metal is higher than the thermal expansion of the glass like with the Housekeeper seal, a high contact angle (bad wetting) means that there is a high tensile stress in the surface of the glass near the metal. Such seals usually break inside the glass and leave a thin cover of