Session BB4.2

1:45 PM BB4.2
TRIBOLOGICAL RESPONSE OF PLASMA SPRAYED LIQUID CRYSTALLINE POLYMERS. Nicole Wagner, David Otterson, Saifi Usmani, Sanjay Sampath, SUNY - Stony Brook, Dept of Materials Science and Engineering, Stony Brook, NY; Jeffrey Brogan, Poly Therm Corp, Stony Brook, NY.

Liquid crystalline polymers display high temperature resistance while maintaining excellent mechanical properties and chemical resistance. In addition, liquid crystalline polymers have intrinsically low oxygen and water vapor permeability's. Such materials can often be used as barrier coatings at temperatures in excess of 200 C. Thermotropic LCP coatings show strong potential for use in the chemical, pulp and paper, petrochemical, and aerospace industry as moisture-proof seals, liners, and other applications requiring high temperature corrosion resistance. Thermotropic LCP coatings have been successfully produced using plasma spray technology onto metallic and organic substrate materials. Surface engineering by thermal spray represents a practical, efficient, and highly cost effective means of protecting components from the effects of wear, corrosion, and other tribological aspects. In this study, thermotropic liquid crystalline polymer powder was introduced into a DC argon/hydrogen plasma to produce coatings on steel substrates. A design of experiments approach was used to systematically vary the process parameters to produce a range of coating microstructures. The coefficient of friction was determined during sliding wear against stainless steel balls in ball-on-flat tests. Relationships among plasma processing, particle melting, and friction will be discussed in detail.