Principle and process of carburizing and quenching

1. Principle of carburizing and quenching:

The process of carburizing and quenching includes three basic processes: decomposition, adsorption and diffusion

Low carbon steel or low carbon alloy steel (carbon content less than 0.25%) is the main material of carburized parts. If you want to give full play to the advantages of carburizing, you must quench immediately after carburizing. High hardness martensite, retained austenite and a small amount of carbide are the main components of the surface microstructure of the workpiece after carburizing and quenching, while the core structure is low carbon martensite with good toughness or non martensite structure, but ferrite should be avoided as far as possible. The depth of carburized layer generally ranges from 0.8 mm to 1.2 mm, while that of deep carburizing can reach 2 mm or deeper. After carburizing and quenching, the surface of the workpiece will produce corresponding compressive internal stress, which is beneficial to improve the fatigue strength of the workpiece. Therefore, improving the strength, impact toughness, wear resistance and prolonging the service life of parts are the ultimate goal of quenching in most enterprises. Therefore, carburizing and quenching process is widely used in all walks of life.

2. Carburizing and quenching process

Induction hardening and low temperature tempering after carburizing

Organization: it can refine the structure of the permeating layer and the part near the permeating layer.

Scope of application: various gears and shafts.

Performance features: small quenching deformation, no need to prevent seepage in advance.

Direct quenching and low temperature tempering

Structure: can not refine the grain size of steel.

Scope of application: Gas Carburizing and liquid carburizing.