Nitridöintiprosessi

Nitridöintiprosessi, often translated as nitriding, is a thermochemical surface hardening process used to increase the hardness, wear resistance, and fatigue strength of steel and other ferrous alloys. The process involves diffusing nitrogen into the surface of the material at elevated temperatures, typically between 450 and 600 degrees Celsius. This diffusion creates a hard, nitrogen-rich layer, known as the nitride layer or case, on the surface.

There are several methods for carrying out nitriding. Gas nitriding is a common technique where the parts are heated in a nitrogen-rich atmosphere, usually ammonia gas (NH3). The ammonia dissociates at high temperatures, releasing nitrogen atoms that diffuse into the steel's surface. Another method is salt bath nitriding, where the components are immersed in a molten salt bath containing nitrogen-bearing compounds. Plasma nitriding, also known as ion nitriding, uses a plasma-generated glow discharge in a nitrogen-containing atmosphere to facilitate nitrogen diffusion.

The depth and hardness of the nitride layer depend on factors such as the type of steel, the nitriding temperature, the duration of the process, and the specific nitriding medium used. Nitrided components exhibit excellent wear resistance due to the formation of hard iron nitrides. The process can also improve corrosion resistance, particularly in certain alloy steels. Nitriding is often chosen for applications requiring high surface hardness and durability, such as gears, crankshafts, dies, and cutting tools. The process is typically performed after heat treatment and machining, as it causes minimal distortion.