United States Patent 8, 277,688, October 2, 2012 (PAX 81) and PTO Application filed June 1, 2012

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1 Active Aluminum Rich Coatings United States Patent 8,262,938, September 11, 2012 (PAX 53) Aluminum Alloy Coated Pigments and Corrosion-Resistant Coatings United States Patent 8, 277,688, October 2, 2012 (PAX 81) and PTO Application filed June 1, 2012 Oxide Coated Metal Pigments and Film-Forming Compositions United States Patent Application 13/564,341, filed August 1, 2012 (PAX 115) Coated Aluminum Alloy Pigments United States Patent Application 13/628,232, filed September 27, 2012 (PAX 121) Technology and Background: Corrosion-inhibiting primers containing hexavalent chromium have been used for the protection of aluminum and other metals on aircraft and other applications for at least 100 years. Once the health issues of hexavalent chromium were identified, alternatives were sought. Over the past 30 years alternative products have been introduced but none have been proven to be equal to or better than primers using hexavalent chromium inhibitors for aircraft operating in the naval environment. An additional challenge is the galvanic interaction of aluminum with other materials it contacts on typical aircraft. Even though primers with hexavalent chromium have been the gold standard for protecting aircraft, they still do not eliminate galvanic corrosion, which has been estimated to be as high as 90% of the corrosion damage on Navy and Marine Corps aircraft. An alternative primer is needed which does not contain hexavalent chromium, is compliant with other health and safety regulations including the amount of volatile organic compounds (VOCs) which are used in the primer, offers general corrosion resistance at least as good as currently used primers, and provides galvanic corrosion resistance which is better than current primers. It is also desirable to have the primer perform well by itself and with other coatings like polyurethane topcoats and various sealants, at similar thicknesses as currently used primers to manage weight. Technology Solution: The U.S. Navy has developed a new primer based on active aluminum alloy powder which meets these needs. The primer is designed to provide electrochemical protection to aluminum, steel and

2 other metallic objects on which it is applied, withstand the severe operating environment of Navy aircraft, ships and facilities, as well as any other outdoor environment, and be easy to mix and apply. The primer is compatible with typical surface preparations including aluminum anodize and conversion coating, phosphate coatings on steel, sacrificial coatings, and other primers. It also provides good adhesion and corrosion performance when applied directly to the surface of metals and composites. The active aluminum alloy powders may be added to any suitable resin or binder system including epoxies, polyurethanes, polysiloxanes, polythioethers, polysufides, silicates, titanates and zirconates. Initial research and development has been focused on optimizing a primer for the protection of aluminum which meets the requirements of MIL-PRF Current formulations show performance that is as good as MIL-PRF primers based on hexavalent chromium on standard 2024-T3 and 7075-T6 aluminum panels tested in ASTM B117 (neutral salt fog) and ASTM G85 Annex 4 (SO 2 salt fog) and superior performance on galvanic test assemblies with titanium and stainless steel fasteners in 2024-T-3 and 7075-T6 aluminum. Performance of these primers in outdoor exposure at the beachfront test site at Kennedy Space Center is not completed but is confirming excellent lab performance on both standard panels and galvanic test assemblies. Additional R&D is underway to optimize the primer as a replacement for zinc-rich primers on steel. If successful, key benefits include the reduction of the use of zinc and reduced weight of liquid primer and cured coating. Summary of Benefits: Improved corrosion protection- especially for galvanic interfaces No hexavalent chromium VOC compliant Light weight: 1 mil (0.001 ) thick for aluminum, 3-5 mils thick for steel; 50% lighter than zinc-rich primers Market Opportunities: The inventions are environmentally benign and highly effective corrosion resistant coatings recently developed by the U. S. Navy. They are available for licensing and can be utilized in the following potential areas: Transportation: Automobiles, Trucks, Trains, Boats/Ships, Bicycles, Mopeds, Military Vehicles, Wheels, Engines, Storage Containers Architectural: Window Frames, Furniture, Trim/Siding

3 Aviation: Aircraft, Engines, Support Equipment Facilities: Buildings, Bridges, Poles, Tanks, Pipes, Pumps, Swimming Pools, Guard Rails, FencesFastening: Rivets, Bolts, Nuts, Washers Status and Opportunity: Patents and patent applications are available for license Potential for collaboration with Naval Air Warfare Center Aircraft Division researchers Full text copy of patents and applications are available at Performance on Galvanic Assemblies Before testing: Primer only on left sides, MIL-PRF Type IV polyurethane topcoat over primer on right sides. Left two fasteners in each group are TiAl6V4 and right two are 316 corrosion-resistant steel. Bottom fasteners have scribes through coatings to simulate damage. Substrate is 2024-T3 aluminum. Aluminum was conversion coated with MIL-PRF Type II TCP (non-hexavalent chromium) before primer application. MIL-PRF hexavalent chromium control Aluminum-Rich Primer, epoxy After testing: Assemblies were exposed 500 hours in ASTM B117 neutral salt fog and then coatings and fasteners removed. The Aluminum Rich primer protected the aluminum better than the control. MIL-PRF hexavalent chromium control Aluminum-Rich Primer, epoxy

4 Performance on Standard Scribed Panels (all panels from test matrix 12-9) Before testing: Epoxy-based aluminum-rich primer on 2024-T3 (left 2 panels) and 7075-T6 (right 2 panels) as painted and scribed. All panels conversion coated with MIL-DTL Type II TCP (nonhexavalent chromium) before primer appication. Coatings scribed with mechanical scribe tool through the coating and into the metal substrate. After testing: Panels were exposed 500 hours in ASTM G85 Annex 4 SO 2 salt fog. Performance is similar to MIL-PRF control with hexavalent chromium inhibitor.

5 After testing: A separate set of 7075-T6 panels was exposed for 2000 hours in ASTM B117 neutral salt fog. The aluminum rich primer panels are on the top, MIL-PRF hexavalent chromium primer control panels are on the bottom. The right panel of each set has a standard MIL-PRF-85285, Type IV topcoat. The performance of the aluminum rich primer is slightly better without topcoat and similar to the hexavalent chromium control with topcoat.

6 A set of 2024-T3 panels was exposed for 2000 hours in ASTM B117 neutral salt fog at the same time as the 7075-T6 panels. The aluminum rich primer panels are on the top, MIL-PRF hexavalent chromium primer control panels are on the bottom. The right panel of each set has a standard MIL-PRF , Type IV topcoat. The performance of the aluminum rich primer is better without the topcoat and slightly worse with the topcoat compared to the hexavalent chromium control.