北京交通大学“与大师面对面”名师讲坛系列活动
（机电学院，2014年春季第20周）

【主  题】： Contact Mechanics Analysis and Experimental Investigation of Scuffing Processes胶合过程的接触力学分析和实验研究

【主讲人】： 邹 茜教授，美国奥克兰大学工程和计算机科学学院副院长，汽车摩擦学中心副主任

【时  间】：2014年7月10日（星期四）上午9：00-11：30

【地  点】：机电学院大会议室（机械工程楼Z802B）

【主  办】：研究生工作部

【承  办】：机电学院

 

Dr. Qian(Beth) Zou, Professor, Associate Dean of the School of Engineering and Computer Science and co-director of Automotive Tribology Center at Oakland University. She obtained her BS, MS, and Ph.D. degrees from Tsinghua University in 1992, 1994 and 2001 respectively. From 1994-2001, she was a faculty member of the Department of Precision Instruments and Mechanology at Tsinghua University. She joined Oakland University in 2002 and worked as an assistant professor (2002-2008), associate professor (2008-2014) and professor (2014-present).

Research interest: Comprehensive numerical and experimental investigation of scuffing processes; Fundamentals and applications of nanofluids; Tribology of engine cylinder kits; Friction phenomena in fasteners and joints; Elastohydrodynamic lubrication.

邹茜教授现任美国奥克兰大学工程和计算机科学学院副院长，汽车摩擦学中心副主任，她分别于1992年、1994年和2001年在清华大学获得学士、硕士和博士学位。1994-2001年于清华大学精密仪器系任教；2002后就职于美国奥克兰大学，历任讲师（2002-2008年）、副教授（2008-2014年）和教授（2014年至今）。研究方向为：胶合过程综合数值模拟和实验研究；纳米流体的理论及应用；发动机气缸套的摩擦磨损；紧固件和接头中的摩擦现象；弹流润滑。

Scuffing damage is catastrophic and typically not self-healing. It severely affects the life and reliability of engineering components, such as engine cylinder blocks, flywheels, camshafts, crankshaft, piston rings, and gears. Typical materials used in these components are steel or cast iron. In this project, a series of scuffing tests were performed with 1080 steel, 1050 steel, gray cast iron, ductile cast iron, and ADI to directly investigate their scuffing behavior and to better understand the scuffing mechanisms. In addition to the experimental investigation, contact mechanics and plasto-elastohydrodynamic lubrication (Mixed PEHL) models were used to simulate the surface interactions and to analyze the contact characteristics by taking into account the plastic deformation in the contact area. The evolution of the contact pressure, the film thickness, the contact area ratio, and the subsurface effective plastic strain were calculated to reveal the scuffing mechanisms. The critical values of the subsurface effective plastic strain, the contact area ratio, the film thickness to roughness ratio (λ ratio), and the wear volume were identified to predict scuffing failure. The effects of work hardening, surface roughness, and lubricant on the scuffing resistance were investigated as well. The simulation results were compared with those from the experiments and a better understanding on scuffing processes was obtained through the research work.

磨损破坏一般是具有灾难性，且不会自愈。它严重影响工程部件，如发动机缸体、飞轮、凸轮轴、曲轴、活塞环和齿轮的寿命及可靠性。这些组件通常使用的典型材料是钢或铸铁。在本报告中采用1080钢、1050钢、灰铸铁、球墨铸铁和ADI公司的一系列磨损试验来研究其磨损行为，以便于更好地了解磨损机理。在试验研究之外，还应用接触力学、弹塑性力学和弹流润滑（混合PEHL）模型来模拟表面的相互作用，并且充分考虑到接触区域的塑性变形来分析接触特性。计算接触压力、膜的厚度、接触面积比率及有效塑性应变的演变来揭示磨损机理。通过确定上述参数及磨损量的临界值来预测磨损故障，研究加工硬化、表面粗糙度及耐磨损性的润滑剂对磨损的影响。将仿真结果和磨损试验进行对比，得到最优的结果。