Tecvac Ltd of Swavesey, Cambridge, a member of the Wallwork  Heat Treatment Group,  is launching the new InnerArmor DLC coating system for aerospace  components on Stand D10 , Hall 1 at Farnborough International Airshow. This advanced coating system allows a DLC (diamond-like carbon) coating  to be applied to the internal surfaces of flying parts and aerospace engine components including bores, tubes, pumps and hydraulic cylinders.

InnerArmor, an enhanced plasma coating process, will apply DLC coating up to 50 microns thick to the internal surfaces of tubes and bores up to 3 metres in length. The DLC coatings are inert and environmentally friendly. They can reduce friction losses to very low levels, and provide a very hard corrosion-resistant film.

Tecvac has already identified aerospace coating applications in control systems, fluid engineering, fuel management and delivery and hydraulics systems, and expects to find many other internal applications, especially bores in engine sub-systems where DLC coating has previously proved difficult or impossible to apply.

The InnerArmor process creates DLC surfaces with a 'glass-like' amorphous (non-crystalline) structure, free from pinhole defects, even in tube lengths of 3 metres at aspect ratios of 1:45. This provides internal bores and tubes with very high levels of protection from erosion, scaling and fouling, and prevents adhesion from gases, liquids, powders and slurries.

InnerArmor DLC coatings can be conducting or insulating, and can withstand high loads at operating temperatures of 450oC. Coating application temperatures for a variety of formulations are below 200oC. This enables many hollow engine parts to be coated with DLC, and allows the replacement of expensive high performance alloys with lower specification steels.

Tests with the new InnerArmor DLC process demonstrated superlative corrosion resistance and wear performance, and consistent film hardnesses of 3000 HV. High performance was shown in salt spray tests to meet US standards. Very high wear resistance in these tests was indicated by a very low attrition rate of less than 0.0005 microns per hour. Tecvac can coat internal bores to thicknesses of between 5 and 50 microns.  More information at  http://www.cmprnews.co.uk/tecvac/farnborough/