Pot metal
Encyclopedia
Pot metal, also known as monkey metal, white metal
or die-cast zinc, is a slang term that refers to alloy
s that consist of inexpensive, low-melting point metals used to make fast, inexpensive castings.
There is no scientific 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. Due to its low melting temperature no sophisticated foundry equipment is needed and specialized molds are not necessary. It is sometimes used to experiment with molds and ideas before using metals of higher quality. Examples of items created from pot metal include toys, furniture fittings, tool parts, electronics components, and automotive parts.
Pot metal can be prone to instability over time, as it has a tendency to bend, distort, crack, shatter, and pit with age. The low boiling point of zinc and the fast cooling of the newly-cast part often allow air bubbles to remain within the cast part, weakening the metal. Many of the components of pot metal are susceptible to corrosion from airborne acids and other contaminants, and the internal corrosion of the metal often causes the decorative plating to flake off. Pot metal is not easily glued, soldered
or welded
.
At one time, "pot metal" referred to a copper alloy that was primarily alloyed with lead. 67% Cu, 29% Pb & 4% Sb and 80% Cu, 20% Pb 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 the 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.
White metal
The white metals are any of several light-colored alloys used as a base for plated silverware, ornaments or novelties, as well as any of several lead-base or tin-base alloys used for things like bearings, jewellery, miniature figures, fusible plugs, some medals and metal type.Some of the metals...
or die-cast zinc, is a slang term that refers to alloy
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...
s that consist of inexpensive, low-melting point metals used to make fast, inexpensive castings.
There is no scientific metallurgical standard for pot metal; common metals in pot metal include zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
, lead
Lead
Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...
, copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
, tin
Tin
Tin is a chemical element with the symbol Sn and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to both neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4...
, magnesium
Magnesium
Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...
, aluminium
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
, iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
, and cadmium
Cadmium
Cadmium is a chemical element with the symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Similar to zinc, it prefers oxidation state +2 in most of its compounds and similar to mercury it shows a low...
. The primary advantage of pot metal is that it is quick and easy to cast. Due to its low melting temperature no sophisticated foundry equipment is needed and specialized molds are not necessary. It is sometimes used to experiment with molds and ideas before using metals of higher quality. Examples of items created from pot metal include toys, furniture fittings, tool parts, electronics components, and automotive parts.
Pot metal can be prone to instability over time, as it has a tendency to bend, distort, crack, shatter, and pit with age. The low boiling point of zinc and the fast cooling of the newly-cast part often allow air bubbles to remain within the cast part, weakening the metal. Many of the components of pot metal are susceptible to corrosion from airborne acids and other contaminants, and the internal corrosion of the metal often causes the decorative plating to flake off. Pot metal is not easily glued, soldered
Soldering
Soldering is a process in which two or more metal items are joined together by melting and flowing a filler metal into the joint, the filler metal having a lower melting point than the workpiece...
or welded
Welding
Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material that cools to become a strong joint, with pressure sometimes...
.
At one time, "pot metal" referred to a copper alloy that was primarily alloyed with lead. 67% Cu, 29% Pb & 4% Sb and 80% Cu, 20% Pb 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 the 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.