HF (IC-VPS )

Most versatile electrode-free thermal spray process for the highest quality, reliability and durability to the exclusion of oxygen at low pressure inert gas atmosphere.

Key characteristics

• The plasma gas Ar, Ar/H2, Ar/H2/He it is without electrodes by an RF coil ionized. The plasma jet is laminar and has a much smaller exit velocity as the plasma jet from a DC plasma torch.
• Contrary to the DC plasma spraying, by the RF plasma spraying the coating powder is injected in axial way through the stationary plasma torch. Result, a much better heat transfer to the spray powder.
• This can also be processed refractory materials such as tungsten and produce very dense coatings.

Process characteristics:

• The plasma spray process produces enough energy to melt refractory materials such as tungsten.
  The arc operates without electrodes, so that contamination from electrode consumption in the sprayed layer does not exist.
• Axial powder injection generates very thick and dense layers.
  Because of its design, the torch is stationary, so that the substrate must be moved in the spray jet.
• The process is conducted in a vacuum chamber. The vacuum chamber is evacuated by a pump system before the process starts, to a pressure level of 0.08mbar. This ensures that residual oxygen or water vapor adhering to the chamber influence the high-purity gas atmosphere. Oxide free and dense layers on a pressure level of 200-400mbar may be applied under inert gas.