Quenching and tempering treatment of seamless steel pipe

Quenching and tempering treatment of seamless steel pipe After the quenching and tempering treatment of seamless pipes, the parts produced have good comprehensive mechanical properties and are widely used in various important structural parts, especially those connecting rods, bolts, gears and shafts that work under alternating loads. But the surface hardness is low and not wear-resistant. Tempering + surface quenching can be used to improve the surface hardness of parts. Its chemical composition contains carbon (C) content of 0.42~0.50%, Si content of 0.17~0.37%, Mn content of 0.50~0.80%, and Cr content<=0.25%. Recommended heat treatment temperature: normalizing 850°C, quenching 840°C, tempering 600°C. Common seamless steel pipes are generally made of high-quality carbon structural steel, which is not very hard and easy to cut. It is often used in molds to make templates, tips, guide posts, etc., but heat treatment is required. 1. After quenching and before tempering, the hardness of the steel is greater than HRC55, which is qualified. The highest hardness for practical application is HRC55 (high frequency quenching HRC58). 2. Do not use the heat treatment process of carburizing and quenching for steel. After quenching and tempering, the parts have good comprehensive mechanical properties and are widely used in various important structural parts, especially those connecting rods, bolts, gears and shafts that work under alternating loads. But the surface hardness is low and not wear-resistant. 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 carbon content on the surface is 0.8-1.2%, and the core is generally 0.1-0.25% (0.35% is used in special cases). After heat treatment, the surface can obtain very high hardness (HRC58–62), and the core has low hardness and impact resistance. Post time: Dec-16-2022