Nanostructured CVD Tungsten Carbide Coating on Aircraft Actuators and Gearbox Shafts Reduces Oil Leakage and Improves Durability

Wear and corrosion of aircraft actuator parts and helicopter gearbox rotating shafts and also wear of seals working against these parts can lead to oil leaks, requiring expensive maintenance and increasing risk of failure.

The Hardide nano-structured CVD Tungsten Carbide coatings can help reduce oil leakage from gearboxes and actuators and increase maintenance intervals. The coating protects metal pistons and shafts from abrasion and corrosion, keeping their surface Ra, Rz and other parameters in optimum ranges for longer, this reduces seal wear and makes the whole unit more durable and reliable.

The coating was qualified by Airbus as an environmentally-friendly replacement for Hard Chrome plating. The coating has enhanced wear resistance outperforming Hard Chrome by 14x and HVOF WC-Co(12%) by 3x. The fine-grain coating nano-structure wears uniformly so even worn Hardide coating shows no hard micro-grains asperities abrasive for seals. The coating is free from porosity and from Cobalt binder and is an excellent barrier against corrosion. As a result the coating keeps the optimal seal-friendly surface finish for longer service even in abrasive and corrosive environments.

The 50-100 microns thick CVD Hardide coating can be applied uniformly on internal and external surfaces and has enhanced fatigue and anti-galling properties.