The Sliding Wear and Friction Behavior of M50-Graphene Self-Lubricating Composites Prepared by Laser Additive Manufactur
- PDF / 8,249,774 Bytes
- 12 Pages / 593.972 x 792 pts Page_size
- 28 Downloads / 164 Views
ÓASM International 1059-9495/$19.00
The Sliding Wear and Friction Behavior of M50-Graphene Self-Lubricating Composites Prepared by Laser Additive Manufacturing at Elevated Temperature Xiyao Liu, Xiaoliang Shi, Yuchun Huang, Xiaobin Deng, Guanchen Lu, Zhao Yan, Hongyan Zhou, and Bing Xue (Submitted August 18, 2017; in revised form December 8, 2017) M50 steel is widely applied to manufacture aircraft bearings where service lives are mainly determined by the friction and wear behaviors. The main purpose of this study is to investigate the tribological behaviors and wear mechanisms of M50-1.5 wt.% graphene composites (MGC) prepared by laser additive manufacturing (LAM) (MGC-LAM) sliding against Si3N4 ball from 25 to 550 °C at 18 N–0.2 m/s. XRD, EPMA, FESEM, and EDS mapping were conducted to understand the major mechanisms leading to the improvement in the sliding behavior of MGC-LAM. The results indicated that MGC-LAM showed the excellent friction and wear performance at 25-550 °C for the lower friction coefficient of 0.16-0.52 and less wear rate of 6.1-9.5 3 1027 mm3 N21 m21. Especially at 350 °C, MGC-LAM obtained the best tribological performance (0.16, 6.1 3 1027mm3 N21 m21). It was attributed to the dense coral-like microstructure, as well as the formed surface lubricating structure which is composed of the upper uniform lubricating film with massive graphene and the underneath compacted layer. Keywords
composites, graphene, laser additive manufacturing, M50
1. Introduction The losses of aerospace bearings caused by friction and wear have seriously affected the performance of aeronautical mechanical systems and even produced some catastrophic consequences (Ref 1, 2). Hence, the urgent need to improve the performance of aerospace bearings has aroused the close attention of researchers all over the world. It is found that using self-lubricating materials is one of the most effective ways to improve the anti-friction and wear properties of bearings in challenging surroundings. Bearings in aerospace applications are mainly fabricated from M50 steel due to the excellent hightemperature strength, thermal fatigue resistance, and thermal stability (Ref 3-5). Consequently, enhancing the tribological and mechanical properties of M50 is a vital and essential for the researchers all over the world. At present, the preparation of metal-based solid selflubricating materials mainly depends on powder metallurgy technology such as spark plasma sintering (SPS) (Ref 6, 7). Essa et al. (Ref 8) investigated the potential tribological benefits of solid lubricating composites WS2-ZnO/M50 prepared by SPS over a wide range of temperatures (from 25 to 800 °C). The results showed that M50-ZnO-WS2 provided the best Xiyao Liu, Xiaoliang Shi, Yuchun Huang, Xiaobin Deng, Guanchen Lu, Zhao Yan, and Hongyan Zhou, School of Mechanical and Electronic Engineering, Wuhan University of Technology, 122 Luoshi Road, Wuhan 430070, China; and Bing Xue, College of Mechanical Engineering, Yellow River Conservancy Technical Institute, Kaifeng 475004, China. C
Data Loading...
