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What are the main heat-resistant components of heat-resistant steel precision castings?


Heat-resistant steel precision castings refer to steels that work at high temperatures. The development of heat-resistant steel precision castings is closely related to the technological progress of various industrial sectors such as power stations, boilers, gas turbines, internal combustion engines, and aero engines. Due to the different temperatures and stresses experienced by various machines and devices, as well as different environments, the types of steel used are also different.
  In order to improve the high temperature oxidation resistance of steel, alloying elements are added to the steel, thereby changing the structure of the oxide. Commonly used alloying elements are chromium, silicon, aluminum and so on. They react with oxygen to form a dense and stable oxide layer on the surface of the steel, or a passivation layer of Cr2O3, SiO2 or Al2O3, etc., to protect the steel from further oxidation. If the amount of chromium, silicon and aluminum added is large, the high temperature oxidation resistance of steel is good, but if the amount of silicon and aluminum added is too large, the mechanical properties and processability of the steel will be deteriorated. Therefore, heat-resistant steel uses chromium as the main alloying element and silicon and aluminum as auxiliary elements. In short, the high-temperature oxidation resistance of steel is only related to the chemical composition.
  Steel castings have an irreplaceable role in special occasions where the force and impact are relatively large. Especially in machinery manufacturing, metallurgy and chemical industry, transportation, aerospace, aviation and other departments have a wide range of applications.

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