Understand at a Glance: The Differences Between Carburizing and Nitriding Processes in Stainless Steel Surface Treatment
High-purity nitrogen can prevent impurities such as oxygen from affecting the formation of the surface layer during the nitriding process, thereby ensuring stable nitriding quality. Nitrogen generators, utilizing technologies such as pressure swing adsorption and membrane separation, can directly extract high-purity nitrogen from the air without relying on external gas supplies. This not only meets the continuous production requirements of the nitriding process but also reduces gas procurement costs and enhances the flexibility and cost-effectiveness of the production process.
I. Core Differences in Process
The carburizing process involves diffusing carbon atoms into the surface of stainless steel. By heating the material at high temperatures—typically between 900 and 1100°C—the carbon reacts with the surface metal to form hard carbides, significantly increasing the surface hardness after treatment. However, the resulting carburized layer is relatively thick and slightly more brittle. In contrast, the nitriding process involves diffusing nitrogen atoms into the surface under moderate-to-low temperature conditions (500–600°C), forming a nitride layer. The nitrided layer is thinner and exhibits better toughness, while still preserving the base material’s corrosion resistance. The key differences between these two processes lie in the elements being diffused, the treatment temperatures, and the resulting surface structures.
II. Comparison of Treatment Effects
After carburizing, the surface hardness of stainless steel can reach above HRC60, exhibiting outstanding wear resistance. However, high-temperature treatment can lead to grain growth in the substrate, compromising overall toughness and slightly reducing corrosion resistance, thus necessitating subsequent anti-rust treatment. After nitriding, the surface hardness typically ranges from HV800 to 1200, with wear resistance comparable to that achieved through carburizing. Moreover, medium- and low-temperature nitriding does not impair the microstructure of the substrate, and the corrosion resistance remains essentially unchanged. Additionally, nitrided parts demonstrate excellent fatigue resistance, with significantly lower deformation compared to those obtained via carburizing.
III. Application Scenarios of Nitriding Processes
In the field of industrial machinery, nitrided stainless steels are commonly used to manufacture transmission components such as gears, shafts, and bearings. Their high wear resistance and fatigue strength can significantly extend the service life of equipment. In mold manufacturing, cavity surfaces of injection molds and stamping dies, after nitriding treatment, can improve demolding efficiency and enhance mold durability. In the automotive industry, key engine parts such as crankshafts and valves undergo nitriding treatment, enabling them to withstand high-temperature and high-pressure operating conditions. Moreover, nitrided stainless steels are widely employed in industries such as petrochemicals and aerospace—sectors that place stringent demands on both corrosion resistance and mechanical performance.
IV. The Key Role of Nitrogen Generators
The nitriding process has extremely high requirements for nitrogen purity, typically demanding a purity level of 99.99% or higher. High-purity nitrogen can prevent impurities such as oxygen from interfering with the formation of the surface layer during nitriding, thereby ensuring stable nitriding quality. Nitrogen generators, utilizing technologies such as pressure swing adsorption and membrane separation, can directly extract high-purity nitrogen from the air without relying on external gas supplies. This not only meets the continuous production needs of the nitriding process but also reduces gas procurement costs and enhances the flexibility and cost-effectiveness of the production process.
Other areas
Oil storage and pressurized pipeline cleaning and purging of oil and gas wells, nitrogen sealing, nitrogen displacement, solvent recovery.
Used for food preservation and grain storage, pest control, food drying and sterilization, quick freezing of food, etc.
Provide the necessary gas raw materials for the preparation of new energy materials, battery production, and create an inert gas environment.
Ensure the manufacturing of electronic components and the stable operation of equipment, providing gas support for maintenance, combustion assistance, cooling, and other aspects related to thermal power generation equipment.
Nitrogen generator: Prevents oxidation, inhibits bacterial growth, and produces odors in biopharmaceuticals, providing protection throughout the process. Oxygen generator: Provides an oxygen-rich environment.
When signs of fire occur in the goaf or other locations, nitrogen injection is needed for fire prevention. The nitrogen device is lowered into the mine. It is used for annealing protective gas and sintering.
Used in the aerospace composite field, providing the necessary inert atmosphere for the molding and reinforcement processes of large carbon fiber composite wings.
Provide protection for the safety of oil and gas reserves, prevent oxidation, nitrogen sealing, and ensure dust suppression, fire prevention, and nitrogen sealing for coal reserves.