The heat treatment knowledge of GBT 8162 45# seamless steel tube

The recommended heat treatment temperature of GBT 8162 45# seamless steel tube is 850℃ for normalizing, 840℃ for quenching, and 600℃ for tempering.

GBT 8162 45# seamless steel is high quality carbon structural steel. Its hardness is not high and it is easy to cut. 45# steel is often used to make templates, pins and guide posts, but it needs heat treatment.The hardness of GBT 8162 45# seamless steel tube is higher than HRC55 (max. up to HRC62) before quenching is qualified.

GBT 8162 45# seamless steel tube should not adopt the heat treatment process of carburizing and quenching. After the quenching and tempering, the 45# steel parts have good comprehensive mechanical properties, and are widely used in all kinds of important structural parts, especially the connecting rod, bolt, gear and shaft and so on, which work under the alternating load. But the surface hardness is low, and it is not wearable. Quenching and tempering plus surface hardening can be used to improve the surface hardness of 45# steel parts. If GBT 8162 45# seamless steel tube is carburized, the hardened martensite will appear in the core after quenching, which will lose the advantage of carburizing treatment.