Which material is suitable for boiler construction in high-temperature environments?

The most suitable material for boiler construction in high-temperature environments is steel. Steel possesses high-temperature strength, excellent ductility, and the ability to withstand pressure, making it ideal for the construction of boilers that operate under elevated temperatures. It can endure the thermal expansion and stress that occur in such environments, thus ensuring the structural integrity and safety of the boiler system.

Cast iron, while strong and durable, is more brittle than steel and not as effective at high temperatures. It can crack or break under high stress or thermal shock, making it less suitable for high-temperature applications. Aluminum, although lightweight and resistant to corrosion, has a much lower melting point compared to steel and cannot withstand the high stress and temperatures typically found in boilers. Plastic materials are not appropriate for boiler construction due to their inability to handle high pressures and temperatures, as they would deform or fail under these conditions.

Therefore, steel stands out as the most appropriate choice for boiler construction in high-temperature environments, due to its mechanical properties and ability to maintain integrity under operating conditions.