The important elements of 4130 alloy structural steel

     4130 alloy structural steel is a low alloy heat-resistant steel, with good mechanical properties and resistance to hydrogen at room temperature and high temperature. The main alloy elements in steel are molybdenum, chromium, vanadium, silicon, boron ect.
     Alloying element molybdenum is very important in 4130 steel , it greatly improve the thermo strength of the steel, maintaining sufficient strength at high temperature, and can refine the grain and prevent overheating tendencies of 4130 steel.
     However, if only containing molybdenum in steel, the carbon will gather into the graphite and precipitation in the long-term high temperature, the performance deterioration. In order to eliminate this kind of tendency, often while adding chromium in 4130 alloy structural steel.
     Chromium can enhance thermo strength, high temperature oxidation resistance and corrosion resistance of 4130 steel. Because the chromium can be formed oxide film of dense and strong adhesion on the surface of the steel, preventing the internal metal continued to be oxidation or corrosion. In steel the chromium content is higher, then oxide film more dense , antioxidant and corrosion resistance is better.

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