Design and preparation of gradient graphite/cermets self-lubricating composites

作     者：Liming Zhou Ji Xiong Zhixing Guo Junliu Ye 

作者机构：School of Manufacturing Science and EngineeringSichuan University 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2018年第34卷第8期

页      面：1378-1386页

核心收录：

学科分类：07[理学] 0817[工学-化学工程与技术] 0806[工学-冶金工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0802[工学-机械工程] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：financially supported by the Nation Natural Science Foundation of China (Grant No.51575368) 

主　　题：Graphite/cermets self-lubricating material Graded structure Finite element analysis Mechanical properties Tribological performance 

摘      要：Based on the functionally graded materials （FGMs） design concept, the laminated-graded graphite/cermets self-lubricating composite was prepared to achieve the integration of mechanical prop- erties and lubrication performance of the cermet. The effects of the layer number and thickness of graded structure on residual stresses in the gradient composites were investigated by finite element method （FEM）. From the FEM analyses, the optimal gradient structure design was obtained correspond- ing to the following parameters： the number of graded layers n = 2 and the thickness of graded structure t = I ram. According to the optimum design, a graded graphite/cermets self-lubricating material with two layers was fabricated by a typical powder metallurgy technique. Compared with the homogenous graphite/cermets composite, the surface hardness and indentation fracture toughness of graded compos- ite were increased by approximately 15.9% and 6.3%, respectively. The results of X-ray diffraction （XRD） stress measurement identified the existence of residual compressive stress on the surface of graded com- posite. Additionally, the friction and wear tests revealed that the wear resistance of the graphite/cermets self-lubricating composite was improved significantly via the graded structural design, whereas the coefficient of friction changed slightly.