Effect of Nitrogen on Austenitic Stainless Steel

The influence of nitrogen on Austenitic stainless steel

Austenitic stainless steel is a kind of steel with many advantages and wide application. It’s widely used in many areas such as engineering, chemical industry, food processing, etc. due to its excellent mechanical properties, corrosion resistance and heat resistance. Austenitic stainless steel is a ferritic stainless steel, and nitrogen is known to have an important influence on the mechanical properties of austenitic stainless steel. The presence of nitrogen in austenitic stainless steel can improve the mechanical properties of austenitic stainless steel, such as strength, creep strength, toughness, fatigue strength, and wear resistance. This kind of steel is widely used in many areas due to its excellent properties.

The presence of nitrogen in austenitic stainless steel will also result in a decrease in the resistivity of the steel. This is because nitrogen atoms in the lattice are electron donors, which cause a decrease in the resistivity of the steel. The decrease in the resistivity of austenitic stainless steel will improve its corrosion resistance. In addition, the presence of nitrogen atoms in austenitic stainless steel will also increase its ductility, which is favorable for its fabrication process.

When nitrogen content in austenitic stainless steel is above 0.2%, the precipitation of hardening elements, such as Cr2N and Mn2N, will be significantly increased. The precipitation of these hardening elements will decrease the ductility of austenitic stainless steel and increase its strength, hardness and wear resistance. However, too high content of nitrogen in austenitic stainless steel will decrease its corrosion resistance, which is not conducive to its application. Therefore, the nitrogen content in austenitic stainless steel must be strictly controlled.

In addition, the addition of nitrogen to austenitic stainless steel can also improve its thermal stability. Nitrogen atoms can form nitrogen pacifying nanostructure during the process of heat treatment and solid solution, which can reduce the precipitation of chromium carbide and improve the thermal stability of austenitic stainless steel. This is especially important for austenitic stainless steel used in high temperature environment.

In summary, nitrogen has an important influence on the mechanical properties of austenitic stainless steel, such as strength, creep strength, toughness, fatigue strength, resistance, etc. The presence of nitrogen in austenitic stainless steel can also improve its corrosion resistance, ductility and thermal stability. Therefore, it is necessary to strictly control the content of nitrogen in austenitic stainless steel in order to get the best performance.

Nitrogen on Austenitic Stainless Steel

Nitrogen is one of the most important alloying elements in austenitic stainless steel, a type of steel that contains at least 18% chromium, 8% nickel and 8-10% molybdenum. In stainless steels, nitrogen is used to increase the hardness, strength and corrosion resistance. Addition of nitrogen also increases the range of working temperatures up to just over 300°C.

The effect of nitrogen on austenitic stainless steels, however, is complex. Most of the nitrogen is added as nitride precipitates of iron, chromium and nickel. The size of the nitride precipitates affects the mechanical properties, grain size and corrosion resistance. Furthermore, the amount of nitrogen added to the austenitic stainless steel affects the other alloying elements and can change the phase of the steel. Too much nitrogen can make the steel brittle, reducing its ductility and weldability.

The amount of nitrogen in austenitic stainless steel can be controlled by careful selection of the raw materials and by adjusting the concentration of nitrogen in the steel during the production process. To ensure consistent results, nitrogen must be monitored closely throughout the entire production process.

Austenitic stainless steels with an increased nitrogen content can offer new properties and applications. This type of steel is ideal for applications that require higher strength, greater corrosion resistance and improved creep resistance. Typical applications include process machinery, pressure vessels and food-processing equipment.