Principle of carburizing multi-purpose furnace

Principle of carburizing multi-purpose furnace

On the one hand, the nitrogen infiltrated into the steel forms iron nitride with different nitrogen content from the surface to the inside, and on the other hand, it combines with the alloy elements in the steel to form various alloy nitrides, especially aluminum nitride and chromium nitride. These nitrides have high hardness, thermal stability and high dispersion, so that the nitriding steel can obtain high surface hardness, wear resistance, fatigue strength, bite resistance, atmospheric and superheated steam corrosion resistance, tempering softening resistance, and reduce notch sensitivity. Compared with the carburizing process, the nitriding temperature is relatively low, so the distortion is small, but because the hardness of the heart is low, the infiltration layer is also shallow, usually can only meet the wear resistance and fatigue resistance requirements of light and medium loads, or there are certain heat resistance and corrosion resistance requirements of the machine parts, as well as various cutting tools, cold and hot work molds. There are many methods of nitriding, the common ones are gas nitriding and ion nitriding.

The research of steel nitriding began in the early 20th century and obtained industrial application after the 1920s. Initially, gas nitriding was limited to steel containing chromium and aluminum, and then expanded to other steel grades. Since the 1970s, nitriding has been rapidly developed and improved from theory to process, and the applicable materials and workpieces are also expanding, becoming one of the important chemical heat treatment processes.