Precision seamless pipe hardness and hardness change after heat treatment Precision seamless pipe is high-quality carbon structural steel, which is not high in hardness and easy to be machined. It is commonly used in molds as templates, tips, guide posts, etc., but requires heat treatment.

No. 45 steel should not be heat treated by carburizing and quenching. After quenched and tempered parts have good comprehensive mechanical properties, they are widely used in various important structural parts, especially those connecting rods, bolts, gears that work under alternating loads, but the surface hardness is low, and they are not wear-resistant. Quenching and tempering can be used to improve the surface hardness of parts.

Carburizing treatment is generally used for heavy-duty parts with surface wear resistance and core impact resistance, and its wear resistance is higher than that of quenching and tempering. If carburizing with 45 # steel, hard and brittle martensite will appear in the core after quenching, losing the advantages of carburizing treatment. The materials that use the carburizing process now have low carbon content, which can reach very high at 0.30%, which is rare in applications.