Stainless steel carburizing and nitriding are two different surface treatment processes, and their differences are mainly reflected in the following aspects:

Treatment principle

Carburizing: Place stainless steel in a carbon-rich medium and heat it to a high temperature, so that active carbon atoms penetrate into the stainless steel surface to obtain a high-carbon carburized layer structure. After quenching and low-temperature tempering, the surface has high hardness, wear resistance and fatigue resistance, and the core still maintains sufficient strength and toughness.

Nitriding: Heat stainless steel to a certain temperature in a nitrogen-containing medium, so that active nitrogen atoms penetrate into the stainless steel surface to form a nitrogen-rich hardened layer. Nitrogen atoms form nitrides with alloying elements in stainless steel, thereby improving surface properties.

Treatment temperature

Carburizing: Usually carried out at high temperatures, the general treatment temperature range is 900-950℃. High temperature helps the diffusion of carbon atoms, allowing them to penetrate a certain depth into the stainless steel surface.

Nitriding: The treatment temperature is relatively low, generally between 500-650℃. Lower temperatures can reduce the deformation of stainless steel and maintain the dimensional accuracy of parts.

Surface properties

Hardness: The surface hardness is higher after nitriding treatment, generally reaching HV800-1200, while the surface hardness after carburizing treatment is usually HRC58-63 (about HV600-700).

Wear resistance: Since the nitride formed by nitriding has high hardness and good stability, the wear resistance of stainless steel after nitriding is better than that of carburizing treatment.

Corrosion resistance: Nitriding can significantly improve the corrosion resistance of stainless steel, especially in some specific corrosive environments. However, if the carburizing process is improper, the corrosion resistance of stainless steel may be reduced.

Processing time

Carburizing: Since carbon atoms need to be fully diffused at high temperature, the processing time is relatively short, generally several hours.

Nitriding: The diffusion rate of nitrogen atoms is slow, and the nitriding process takes a long time, which may take more than ten to dozens of hours.

Application scenarios

Carburizing: It is often used for parts that bear large impact loads and wear, such as gears, shafts, etc., to improve their surface hardness and wear resistance, while ensuring that the core has sufficient toughness.

Nitriding: Suitable for parts that require high dimensional accuracy, high hardness, wear resistance and corrosion resistance, such as precision engine parts, molds, etc.