SBIR-STTR Award

This SBIR project aims to demonstrate a manufacturing process for erosion-resistant coatings for large-diameter IBR and lift-fan blades using an advancement PVD. High-Power Impulse Magnetron Sputtering employing a "Positive Kick" is a new PVD technique that imparts controlled ion energy into the growing film for densification, adhesion, stress control/relief, smoothness and composite metal/ceramic layering. The positive voltage reversal in the presence of dense HiPIMS plasma leads to quasi-conformal sheath coverage on substrates for deposition onto 3D structures and shapes with a single processing system-ideal for the 3D complex IBR and lift-fan structure. Extremely thick multilayer nanocomposite stacks in excess of 100um have been deposited with improved smoothness, lubricity, fracture toughness and ultra-hardness with corrosion resistance. This new technique mitigates the macroparticle problems of cathodic arc, allows deposition of insulating materials with energetic ion control, increases deposition rate and allows stress control. Phase I will demonstrate production of prototype materials for basic functionality testing with pathway for manufacturing scale up in Phase II using large sputtering cathodes for IBRs and lift fan blades.

Military aircraft, such as the F-35, C-130 and RQ/MQ-4, can operate in sandy/dusty or salt spray maritime environments and will ingest abrasive particles during the critical take-off and landing stages of operation—as well as experience water droplet impacts under high-speed flight. This results in severe erosion and corrosion of the gas turbine compressor airfoils that deteriorates engine performance, lowers safety, increases fuel consumption and maintenance/logistics support, and increases cost per flight hour. Advanced erosion-resistant coatings and novel manufacturing methods to apply such coatings on large (~1-m diameter) 3D integrally-bladed rotors (IBRs) and lift-fan blades are needed. IBRs are high-value, high-consequence components that are expensive to manufacture and replace; therefore, there is commercial potential for novel coating and application systems that can maintain IBR/lift-fan efficiency, increase aircraft availability and lower overall cost of ownership. Engine failures are costly such as the 2013 IBR failure and accelerated ground test failures. The specific need is a coating that can provide both sufficient leading-edge erosion and corrosion protection and can be applied on large titanium airfoil and integrated blade-rotor castings and additively manufactured parts. Such ‘agnostic’ technology could be applied to other military engines, such as Rolls-Royce AE2100 and AE3007, as well as large diameter fan leading-edge components including lightweight CMC’s. If the novel solution can be ported for other aircraft and industrial gas turbine applications, there is an SBIR win-win commercial success. There are opportunities to increase blade leading edge lifetime (maintain engine power, longer time-on-wing), improve surface roughness (air flow and fuel efficiency), and improve resilience (corrosion environments) leading to cost savings. Over the past 20 years, thin-film coatings applied directly on individual (removable) small blades via atmospheric plasma spray or cathodic arc deposition have resulted in cost savings and improved “time on wing” for the DoD mission. The shift to large-diameter “blisks” for tighter tolerance and improved engine efficiency necessitates new/improved deposition techniques and coating methods for these challenging 3D large-aspect geometries. A novel technique using next-generation high-power impulse magnetron sputtering was demonstrated. The IMPULSE + Positive Kick enables highly conformal, nanolayer coatings with controlled film morophology for superior erosion resistance and corrosion projection--potentially solving the critical challenge is to coat large 3D-shaped IBR and compressor blades with film conformality and the desired morphology, crystallinity, and physical properties (i.e., nano-hardness, ductility, stress, chemical resistance, porosity, crack arrest, etc.).