Surface Technology Coatings introduced Australia’s first commercial plasma nitriding facility in 2002. The revolutionary NitroPlas system generates a plasma on a large cage surrounding the entire workload in a vacuum furnace. The workload is uniformly and efficiently heated by the cage. Problems associated with conventional plasma nitriding, where the plasma is generated on the parts, such as overheating by the hollow cathode effect and damage caused by arcing are thus greatly reduced.

The NitroPlas layer is hard and tough reducing the need for post-treatment grinding. The nitride precipitates produced in the diffusion zone are smaller and more evenly dispersed than those produced by gas nitriding which considerably improves the toughness and fatigue properties when using NitroPlas.

NitroPlas Benefits

  • Reduction of post-nitriding grinding
  • Minimal corner and edge chipping
  • Minimum distortion
  • Reliable, reproducible results every time
  • Cost effective
  • Environmentally friendly
  • Effective masking
  • Faster turnaround and reduced down time
  • Full metallographic analysis and QA
  • Post NitroPlas treatments available

Suitable Materials

  • Most alloy steels containing chromium and molybdenum, eg 4140, 4340
  • High alloy steels also containing aluminium, tungsten and vanadium, eg DIN 1.8550
  • Austenitic and martensitic stainless steels, eg 300 and 400 series
  • High speed steels, eg M2, M42, T15
  • Cast irons
  • Plastic mould steels, eg P20
  • Sintered or powder metallurgy materials, eg ASP 23
  • Cold work steels, eg D2, A2
  • Hot work steels, eg H11, H13


  • Aluminum extrusion dies
  • Nuts and bolts
  • Aerospace components
  • Press tools
  • Machine tool spares
  • Automotive components
  • Plastic extrusion and injection moulding tools
  • Forging dies
  • Tool holders
  • Valve and pump components
  • Shafts and gears
  • Rollers
  • Ejector pins
  • Die casting dies
  • Sintered components