What material is primarily used in the construction of a cast iron boiler?

The primary material used in the construction of a cast iron boiler is indeed cast iron. This material is favored for its excellent properties, which include high durability, resistance to thermal shock, and good corrosion resistance, making it ideal for withstanding the high-pressure and high-temperature conditions often found in boiler applications.

Cast iron also provides superior heat retention, which enhances the efficiency of boilers by allowing for a steady release of heat. The design of cast iron is typically suited for the heavy-duty requirements of industrial or residential heating systems, making it a conventional choice in the industry.

While aluminum, steel, and copper are also materials used in boiler construction, they do not match the specific advantages and traditional applications of cast iron in boiler manufacturing. Steel, for example, may be used in other types of boilers but does not hold the same performance characteristics as cast iron for specific heating applications.