Corrosion Resistant Nanocomposite Coatings: A Lower Cost Alternative to Grit Blasting

The cost of coating and maintaining Navy ships is substantially high and can be reduced by eliminating the expensive grit blasting step and reducing the thickness of epoxy primer for maintaining the same operational life of corrosion-resistant coating system. Grit blasting of Navy ships, a routine surface preparation methodology, is expensive and generates a large amount of hazardous waste. Alternative surface preparation techniques that can provide excellent adhesion to corrosion resistant coatings applied over metallic surfaces are needed. In the Phase I program, aluminum alloy and mild steel panels were treated with a thin nanocomposite non-chromate pretreatment as a feasible alternative to abrasion (or grit) blasting. Corrosion test results and preliminarily cost analysis indicated that nanocomposite pretreatment is a viable solution as a replacement for grit blasting. In Phase II, technical challenges in implementing the nanocomposite pretreatment technology on a large scale will be addressed. Optimization of the pretreatment chemistry will also be conducted in the Phase II program along with a detailed analysis of the corrosion performance on both mild steel and aluminum alloy surfaces. The Phase II program will lay the foundation for a commercialization effort where we will initiate large scale production of the pretreatment to cater to the needs of the Navy and other industrial applications.