Welcome to Acta Armamentarii ! Today is Share:

Acta Armamentarii ›› 2021, Vol. 42 ›› Issue (4): 715-722.doi: 10.3969/j.issn.1000-1093.2021.04.005

• Paper • Previous Articles     Next Articles

The Effect of Metal Doping on the Friction Performance of DLC Coating for Piston Pins of Highly-strengthened Diesel Engine

GUO Shenggang1, WANG Jianping2, ZHAO Zhongcheng1, CHENG Jingjing2, TIAN Xinwei1   

  1. (1.State Key Laboratory of Engine Reliability,Weichai Power Co.,Ltd., Weifang 261001, Shandong, China;2.School of Mechanical Engineering, Anhui Polytechnic University, Wuhu 241000, Anhui, China)
  • Online:2021-06-08

Abstract: The piston pins of diesel engine are subjected to periodically the alternating mechanical and thermal loads, and the abnormal wear and tear often occur due to adhesion. In order to improve the friction and wear performances of piston pin of diesel engine, the diamond-like carbon (DLC) coating of three doped metals (Cr, W, Cr+Ti) was deposited on the surface of piston pin by magnetron sputtering method, the scanning electron microscope (SEM), X-ray diffractometer (XRD) and energy disperse spectroscopy (EDS) were used to analyze the micro-morphologies and structures of different DLC coating surfaces, and the friction and wear properties and film-based bonding strength were tested. The results show that the surface micro-morphologies of the three coatings are similar, their surfaces are dense without obvious defects and holes, but a small amount of particles are formed on the surfaces. Compared with Cr-doped DLC coating, the surface is smoother. For Cr-doped DLC coating, Cr exists as Cr element and Cr C compound, which greatly improves the mechanical properties of Cr; DLC coating doped with Cr has higher film-based bonding strength and better friction performance. The performance of DLC coating doped with Cr and Ti is similar to that of Cr-doped DLC coating. Cr and Ti exist in the form of element and CrC and TiC compounds. W-doped DLC coating has high brittleness and poor toughness due to the formation of WC compound.

Key words: pistonpinofdieselengine, metal-dopedcoating, diamond-likecarbon, frictionandwear, bondstrength, micro-morphology

CLC Number: