When making pot metal, all the metals are melted together. This action alters the properties of each of the metals included in the mix, which gives the outcome (pot metal) a low melting point. It's for the same reason that this type of zinc-rich hybrid metal is weak and has a low melting point.

Is pot metal durable?

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.

Is pot metal soft?

Pot metal is, essentially, a mix of non-ferrous metal scraps that have been thrown into a “pot” and melted down to create inexpensive castings and parts. Varying metals are utilized in these blended alloys including zinc, copper and lead, and the resulting “pot metal” is very soft and melts at a low temperature.