45# seamless steel pipe

45# seamless steel pipe

　　45# seamless steel pipe after quenching and tempering treatment has good comprehensive mechanical properties and is widely used in various important structural parts, especially those connecting rods, bolts, gears and shafts working under alternating load. However, the surface hardness is low and not wear-resistant. Quenching and tempering + surface quenching can be used to improve the surface hardness of parts.

　　The quenched and tempered parts have good comprehensive mechanical properties and are widely used in various important structural parts, especially those connecting rods, bolts, gears and shafts working under alternating load. However, the surface hardness is low and not wear-resistant. Quenching and tempering + surface quenching can be used to improve the surface hardness of parts.

　　Carburizing treatment is generally used for heavy-duty parts with wear-resistant surface and impact resistant core, and its wear resistance is higher than quenching and tempering + surface quenching. The surface carbon content is 0.8-1.2%, and the core is generally 0.1-0.25% (0.35% in special cases). After heat treatment, the surface can obtain high hardness (HRC58-62), the core has low hardness and impact resistance.

　　If 45 steel is carburized, hard and brittle martensite will appear in the core after quenching, which will lose the advantage of carburizing treatment. The carbon content of materials with carburizing process is not high, and the core strength can reach very high at 0.30%, which is rare in application. 0.35% have never seen examples, which are only introduced in textbooks. The process of quenching and tempering + high frequency surface quenching can be adopted, and the wear resistance is slightly worse than carburizing.