Casting is a metal hot working process that humans have mastered relatively early, with a history of about 6000 years. China has entered the heyday of bronze casting around 1700-1000 BC, and its craftsmanship has reached a considerable level. Casting is the method of casting liquid metal into a casting cavity that is suitable for the shape of the part, allowing it to cool and solidify to obtain the part or blank.  The cast material is mostly a metal that is originally solid but heated to a liquid state (such as copper, iron, aluminum, tin, lead, etc.), while the material of the mold can be sand, metal, or even ceramics. The methods used may vary depending on the requirements.