Pot metal is an alloy of copper and lead, formerly used for making plumbing fixtures, bearings, etc. It is an alloy of low-melting-point metals that manufacturers use to make fast, inexpensive castings. In a nutshell, it is a colloquial term referring to alloys consisting of inexpensive, low-melting-point metals. 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. For starters, an alloy is any metal made by combining two or more metallic elements to have a stronger or corrosion-resistant metal. 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, aluminum, iron, and cadmium. The primary advantage of this 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. Although this metal can consist of a broad spectrum of metals, the primary ingredient in most cases is zinc.
Fig: Pot Metal Plated tube
This action alters the properties of each of the metals included in the mix, which gives the outcome of this metal, a low melting point. If you are not sure whether the metal is aluminum or pot metal, weighing your sample will tell you the difference. 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. This metal is much heavier compared to pure aluminum. Besides, although this metal looks a lot like aluminum, the finish of pot metal leaves some pattern that is not present in aluminum.
Some of the common metals in pot metal include- Copper, Tin, Cadmium, Zinc, Lead, Magnesium, Iron, Aluminum, etc.
This 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. This metal is quite inexpensive compared to other metals.