Future Development Requirements Of Heat-resistant Steel

With the development of social development, science and technology have been developed by leaps and bounds, but it is followed by a series of environmental problems and ecological harmony. Carbon dioxide emissions have a negative impact on the development of current thermal power plants. The research shows that increasing steam pressure and temperature during operation is the most effective way to solve the above problems. The main high-temperature components used in thermal power plants are basically heat-resistant steel, so the development of new heat-resistant steel, improve the use temperature range of heat-resistant steel, and enhance its creep fracture strength at higher temperatures has been a hot focus of research in the field of metallurgy, power and materials.
The continuous casting of heat-resistant steel can not only improve the recovery rate of molten steel, save the reworking process, greatly reduce energy consumption, and significantly improve the production efficiency. The structure of continuous casting is uniform, the segregation is small, and the labor intensity of continuous casting is low. Therefore, continuous casting is an important measure to improve the quality and reduce the cost of heat-resistant steel production, and it is also one of the important signs of modern production. Heat-resistant steel continuous casting has higher requirements than ordinary steel continuous casting in the process and equipment, such as heat-resistant steel continuous casting on the temperature and chemical composition of molten steel requirements are very strict, and requires the casting temperature to be controlled in a relatively narrow range, in order to prevent secondary oxidation. In the process of continuous casting, it is required to adopt no oxidation protection casting, and heat-resistant steel continuous casting also has strict requirements on refractory materials used in ladle, tundish, sliding nozzle and intrusion nozzle, etc. In order to improve the solidification structure of the casting, reduce the defects such as inclusions, center segregation, central shrinkage and internal cracking, and obtain high-quality continuous casting. Generally, electromagnetic stirring technology is used, and the cooling process of heat-resistant steel continuous casting is different from that of general steel, especially martensitic steel, which must be cast into the annealing furnace to cool slowly above 300 ° C to prevent martensitic phase transformation and deformation cracks, and the quality requirements of heat-resistant steel continuous casting are much stricter than that of general steel.