['The', 'friction', 'coefficient', 'of', 'composite', 'coating', 'is', 'relatively', 'lower', 'and', 'more', 'stable', 'than', 'what', 'has', 'been', 'reported', 'in', 'literature', '[', '24,25', ']', 'for', 'anodizing', 'coatings', '.']