Various classifications of heat resistant castings

- Nov 06, 2019-

Classified by alloying element content

1) Low carbon steel: In the middle of such steel, it contains or rarely contains other alloying elements, and its carbon content generally does not exceed 0.2%.

2) Low-alloy heat-resistant steel: In this type of steel, one or several alloying elements are contained, but the content is not high. The total amount of alloying elements contained in the steel is not more than 5%, and the carbon content is not more than 0.2%.

3) High-alloy heat-resistant steel: In this type of steel, there are many alloying elements, and the alloying element content is generally above 10%, and even as high as 30% or more.

Classified by steel characteristics

1) Anti-oxidation steel (or heat-resistant steel): This type of steel has good oxidation resistance and high temperature corrosion resistance at high temperature (generally 550 ~ 1200 ° C), and has a certain high temperature strength. It is used to manufacture various types of heating furnace parts and heat exchangers, to manufacture the combustion city of hot steam turbines, boiler squash, heating furnace floor and roller table, and furnace tube. Antioxidant performance is the main indicator and the parts themselves are not subject to great stress.

2) Heat-strength steel: It can withstand considerable additional stress at high temperature (usually 450-900 °C) and has excellent resistance to oxidation and high-temperature gas corrosion. It is usually required to withstand cyclic variable stress. It is commonly used as the rotor and blade of steam turbines, gas turbines, superheaters of boilers, bolts and springs working at high temperatures, intake and exhaust valves of internal combustion engines, petroleum hydrogenation reactors, etc.