1. Faculty of Mechanical Engineering and Automation Zhejiang Sci-Tech University Hangzhou 310018 P. R. China
2. Automotive Tribology Center, Department of Mechanical Engineering, School of Engineering and Computer Science Oakland University Rochester MI 48309 USA
3. Key Laboratory of Automobiles Materials, Department of Materials Science and Engineering Jilin University Jilin 130025 P. R. China
4. College of Mechanical and Automotive Engineering Zhejiang University of Water Resources and Electric Power Zhejiang 310018 P. R. China