Innovative Erosion-Resistant Coating Materials/Concepts for Leading Edges on Composite Rotor Blades

The Navy's helicopters and aircraft encounter dust, salt and water laden environments. The impact of sand and water droplets onto the rotor blades at high velocities causes rotor life to drop drastically. The cost of replacing and maintaining rotor blades is a significant factor. The current solution is to use metallic abrasion strips that offer limited protection. AS&M has been developing a coating that provides superior erosion protection. AS&M's coating is a nano-composite reinforced elastomer with superior erosion resistance. The coating resists erosion by absorbing a part of the impact energy. In Phase I, the applicability of AS&M's coating on composite material was demonstrated. AS&M's coating was found to have adequate adhesion, uniformity, smoothness, high velocity sand erosion and cavitation properties. It was also found to be applicable on a range of substrates - aluminum, stainless steel, nickel, titanium and steel. In Phase II, we propose to further develop the material to improve its thermal conductivity and optimize the composition to demonstrate combined sand and rain erosion resistance in the whirling arm test. The up-scaling capabilities will be established by standardizing the technology-related issues that include specification of raw materials, mixing, spray processing, finishing, field applicability and repair.