Tribological properties of a‐CN_x coatings sliding against SiC balls in ethylene glycol aqueous solution

Abstract

Amorphous carbon nitride(a-CN x ) coatings were deposited on SiC disks by using ion beam assisted deposition, and their bonding structure and hardness were determined using X-ray photoelectron spectroscopy and nano-indenter, respectively. The contact angles on the surface of the a-CN x coatings were measured with contact angle meter. The friction and wear behaviours of the a-CN x /SiC tribopairs in ethylene glycol aqueous solution were investigated with ball-on-disk tribometer. The results indicated that the a-CN x coatings contained 12at. % nitrogen and their bonding structure consisted of sp 2 C=N/C=C and sp 3 C-N bonds. The static contact angles on the a-CN x coatings decreased with the ethylene glycol concentration. The lowest coeffi cient of friction of 0.019 was acquired as the ethylene glycol concentration was 10vol. %. When the ethylene glycol concentration increased, the specifi c wear rate of the SiC ball fl uctuated in the range of 5.9 × 10 −10~1 .1 × 10 −9 mm 3 Nm −1 , while that of a-CN x coatings varied in the range of 3.3 × 10 −8~7 .8 × 10 −8 mm 3 Nm −1 .

Investigation of the running-in process of silicon nitride sliding in aqueous solutions of ethylene glycol

“…The unidirectional sliding running-in test is a simple and effective method to investigate the tribological properties of tribopairs [2,3,5,35,36]. In this study, running-in tests of Si 3 N 4 in different aqueous solutions of ethylene glycol were conducted in a MMW-1 type ball-on-disc tribometer (Puye Mechanical & Electrical Technology Co., Ltd., China).…”

Progress in Tribological Properties of Nano-Composite Hard Coatings under Water Lubrication

“…In principle, the counterpart, which easily reacts with water to form a lubricating and protective film, will decrease the friction coefficient of tribopairs and enhance the wear resistance of coatings intensively [57]. It is for this reason, under the same load and sliding velocity (5 N and 160 mm/s), that the friction coefficient of the a-CN x /Si-based tribopair (0.013~0.017) was much lower than that of the a-CN x /Fe-based tribopair (0.072~0.075), while the a-CN x /Al 2 O 3 tribopair showed the highest friction coefficient (0.10) due to the inertness of Al 2 O 3 in water [58].…”