Crucible is a dish in which materials are melted, heated, boiled, melted, scorched or dried under laboratory conditions. For refractory metals, crucibles are made from refractory materials such as cast iron. Cast iron is an iron alloy with an admixture of 2% carbon and several other elements.
In the metallurgical, metalworking and other heavy industries, cast iron crucibles are used in the shape of a cylinder or a truncated cone. For laboratory analyzes, crucibles in the form of boats or bowls are used. Cast iron crucibles have their own markings indicating the darkness of the cast iron alloy and the volume of the inner cavity. Castings are made of gray cast iron (SCH) alloy and come in small, medium or large sizes. The abbreviation СЧ and the number includes the chemical composition, mechanical and physical properties, hardness, density, use of cast iron alloy.
A cast iron crucible is used for melting light alloys in crucible furnaces, lined from the inside with refractory masonry in a metal casing. The advantage of cast iron crucibles in their strength, the melt using a mixture of fluoride and chloride salts, liquid fluxes, corrodes the base of other crucibles or interacts with their base, contaminating it. Oxidation and contact with gases are relatively small, therefore high quality metal is obtained in cast iron crucibles. The disadvantage is the danger of iron contamination of aluminum alloys with strong overheating of the crucible. Painting the inner surface with a special refractory paint partially prevents the alloy from interacting with the crucible walls.
Prepared using materials from Metals Expert
