Pot metal the caster adds other metals to the mix to strengthen the cast part, improve flow of the molten metal, or to reduce cost. With a low melting point of 419 °C (786 °F), zinc is often alloyed with other metals including lead, tin, aluminium, and copper. Pot metal is generally used for parts that are not subject to high stresses or torque. Items created from pot metal include toys, furniture fittings, tool parts, electronics components, automotive parts, inexpensive jewelry and improvised weaponry. It is also used in inexpensive electric guitars and other budget priced musical instruments. Pot metal Pot metal
Glass-to-metal seal for nickel and iron and their alloys. This is achieved by heating the metal in vacuum or sometimes in hydrogen atmosphere or in some cases even in air at temperatures above those used during the sealing process. Oxidizing of the metal surface also reduces gas evolution. Most of the evolved gas is produced due to the presence of carbon impurities in the metals; these can be removed by heating in hydrogen. The glass-oxide bond is stronger than glass-metal. The oxide forms a layer on the metal surface, with the proportion of oxygen changing from zero in the metal to the