What is "pot metal"

Pot \Pot\, n. [Akin to LG. pott, D. pot, Dan. potte, Sw. potta, Icel. pottr, F. pot; of unknown origin.]

1. A metallic or earthen vessel, appropriated to any of a great variety of uses, as for boiling meat or vegetables, for holding liquids, for plants, etc.; as, a quart pot; a flower pot; a bean pot.

2. An earthen or pewter cup for liquors; a mug.

3. The quantity contained in a pot; a potful; as, a pot of ale. ``Give her a pot and a cake.''
   --De Foe.

4. A metal or earthenware extension of a flue above the top of a chimney; a chimney pot.

5. A crucible; as, a graphite pot; a melting pot.

6. A wicker vessel for catching fish, eels, etc.

7. A perforated cask for draining sugar.
   --Knight.

8. A size of paper. See Pott.

9. marijuana. [slang]

10. The total of the bets at stake at one time, as in racing or card playing; the pool; also (Racing, Eng.) a horse heavily backed; a favorite. [Slang]

11. (Armor) A plain defensive headpiece; later, and perhaps in a jocose sense, any helmet; -- called also pot helmet.

12. (Card Playing) The total of the bets at one time; the pool. Jack pot. See under 2d Jack. Pot cheese, cottage cheese. See under Cottage. Pot companion, a companion in drinking. Pot hanger, a pothook. Pot herb, any plant, the leaves or stems of which are boiled for food, as spinach, lamb's-quarters, purslane, and many others. Pot hunter, one who kills anything and everything that will help to fill has bag; also, a hunter who shoots game for the table or for the market. Pot metal.

    1. The metal from which iron pots are made, different from common pig iron.

    2. An alloy of copper with lead used for making large vessels for various purposes in the arts.
       --Ure.

    3. A kind of stained glass, the colors of which are incorporated with the melted glass in the pot.
       --Knight.

       Pot plant (Bot.), either of the trees which bear the monkey-pot.

       Pot wheel (Hydraul.), a noria.

       To go to pot, to go to destruction; to come to an end of usefulness; to become refuse. [Colloq.]
       --Dryden.
       --J. G. Saxe.

n. 1 The metal from which iron pots are made, different from common pig iron. 2 An alloy of copper with lead used for making large vessels for various purposes in the arts. 3 A kind of stained glass, the colours of which are incorporated with the melted glass in the pot.

1. n. cast iron used for making cooking wares

2. an alloy of copper and lead used especially for making large pots

Pot metal—also known as monkey metal, white metal, or die-cast zinc—is a colloquial term that refers to alloys of low-melting point metals that manufacturers use to make fast, inexpensive castings. The term "pot metal" came about due to the practice at automobile factories in the early 20th century of gathering up non-ferrous metal scraps from the manufacturing processes and melting them in one pot to form into cast products. A small amount of iron usually made it into the castings, but too much iron raised the melting point, so it was minimized.

There is no metallurgical standard for pot metal. Common metals in pot metal include zinc, lead, copper, tin, magnesium, aluminium, iron, and cadmium. The primary advantage of pot metal is that it is quick and easy to cast. Because of its low melting temperature, it requires no sophisticated foundry equipment or specialized molds. Manufacturers sometimes use it to experiment with molds and ideas (e.g., prototypes) before casting final products in a higher quality alloy. Items created from pot metal include toys, furniture fittings, tool parts, electronics components, and automotive parts.

Depending on the exact metals "thrown into the pot," pot metal can become unstable over time, as it has a tendency to bend, distort, crack, shatter, and pit with age. The low boiling point of zinc and fast cooling of newly cast parts often trap air bubbles within the cast part, weakening it. Many components common in pot metal are susceptible to corrosion from airborne acids and other contaminants, and internal corrosion of the metal often causes decorative plating to flake off. Pot metal is not easily glued, soldered, or welded.

At one time, pot metal referred specifically to a copper alloy that was primarily alloyed with lead. Mixtures of 67% copper with 29% lead and 4% antimony and another one of 80% copper with 20% lead were common formulations.

The primary component of pot metal is zinc, but often 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.