What is gas nitriding?
Gas nitriding is a heat-treatment process that diffuses nitrogen into the surface of steel to form a hard nitride layer, improving wear resistance and service life. The nitrogen comes from dissociating ammonia: NH₃ is cracked in a furnace at 550–570 °C into nitrogen and hydrogen, and the nitrogen diffuses into the metal surface to form a nitride layer.
Benefits of gas nitriding
- Surface hardness up to 1400 HV.
- High wear resistance and corrosion resistance.
- Improved fatigue strength.
- Good temper resistance and low distortion; uniform treatment.
Gas nitriding is widely used in automotive, aerospace, watchmaking and tooling industries.
Why control oxygen in gas nitriding furnaces?
Oxygen in the furnace atmosphere can create an explosion risk when ammonia (NH₃) is heated. To minimise this risk, the furnace must first be purged to reduce oxygen – typically below 3–5 %. Nitrogen is the usual purge gas, controlled by a flow meter to supply sufficient furnace volume changes.
Oxygen control solution for nitriding furnaces
The SST Sensing GAP oxygen analyser is ideal for this application: it withstands process temperatures up to +700 °C, has stainless-steel construction, flange connection, LCD display, 4–20 mA output and communications – confirming safe O₂ levels before ammonia is introduced.
Related products and solutions
Where to buy oxygen analysers for heat treatment furnaces?
EQUIPMENT INDUSTRIAL SOLUTION CO., LTD (ISE) – Ho Chi Minh City, Vietnam – supplies genuine oxygen analysers for heat treatment furnaces with technical consulting, fast quotation and on-site commissioning support across Vietnam and Southeast Asia.
Contact us: Sales +84 909 617 185 – Technical +84 979 117 185 – Email: [email protected]
