Improving the wear resistance of automotive clear-coat with addition of precipitated nano silica

In the present research، production and wear characterization of acrylic based polyurethane- precipitated nanosilica clear coats on carbon steel substrates were investigated. Nowadays، acrylic based polyurethane are the largest coatings used for automotive clear-coats. To enhance the dispersion of nanopaticles in polymer matrix، magnetic and high speed mixers were used. Mechanical and wear properties of coatings were evaluated by impact، microhardness and pin on disk wear tests. The results indicated that toughness، hardness and wear resistance were improved by increasing the nano silica content. SEM photographs of wear track illustrated that surface fatigue was the predominant wear mechanism. Finally، it was found that the cheaper and high performance nanocomposite clear coat could to replace with conventional clear coats.