What steel is high temperature resistant?
There are many types of steel, but their functions are not exactly the same.
Generally, we refer to high-temperature steel as “heat-resistant steel”. Heat-resistant steel refers to a class of steels that have oxidation resistance and satisfactory high-temperature strength and excellent heat resistance under high temperature conditions. China began producing heat-resistant steel in 1952.
Heat-resistant steel is often used in the manufacture of components operating at high temperatures in boilers, steam turbines, power machinery, industrial furnaces and industrial sectors such as the aviation and petrochemical industries. In addition to high temperature strength and resistance to high temperature oxidative corrosion, these components also require satisfactory resistance, outstanding processability and weldability, and certain arrangement stability according to different uses.
Heat-resistant steel can be divided into two types according to its function: anti-oxidation steel and heat-resistant steel. Anti-oxidation steel is also called skin steel for short. Hot-strength steel refers to steel that has outstanding oxidation resistance at high temperatures and has high high-temperature strength.
Heat-resistant steel can be divided into austenitic heat-resistant steel, martensitic heat-resistant steel, ferritic heat-resistant steel and pearlite heat-resistant steel according to its normalizing arrangement.
Austenitic heat-resistant steel contains a lot of austenite constituent elements such as nickel, manganese, and nitrogen. When it is above 600 ℃, it has good high-temperature strength and arrangement stability, and has excellent welding function. It is generally used above 600 ℃ Heat intensity data of the operation. Martensitic heat-resistant steel generally has a chromium content of 7 to 13%, and has a high temperature strength, oxidation resistance and water vapor corrosion resistance below 650 ° C, but its weldability is poor.
Ferritic heat-resistant steel contains more elements such as chromium, aluminum, silicon, etc., forming a single-phase ferrite arrangement, has outstanding ability to resist oxidation and high temperature gas corrosion, but has low temperature strength and greater brittleness at room temperature. , Poor weldability. The pearlite heat-resistant steel alloy elements are mainly chromium and molybdenum, and the total amount generally does not exceed 5%.
Its safety excludes pearlite, ferrite, and bainite. This kind of steel has excellent high temperature strength and process function at 500 ～ 600 ℃, and the price is low.
It is widely used to make heat-resistant parts below 600 ℃. Such as boiler steel pipes, turbine impellers, rotors, fasteners, high-pressure vessels, pipes, etc.