Stable and super‐low friction of amorphous carbon nitride coatings in nitrogen gas by using two‐step ball‐on‐disk friction test. (30th January 2014)

• Record Type: Journal Article
• Authors: Wang, Pengfei; Sugo, Masakatsu; Adachi, Koshi
• Is Part Of: Lubrication science. Volume 27:Number 3(2015:Apr.)
• Page Start: 137
• Page End: 149
• Publication Date: 2014-01-30
• Subjects: carbon nitride -- nitrogen gas -- friction coefficient -- running‐in -- pre‐sliding; Tribology -- Periodicals; Lubrication systems -- Research -- Periodicals; Surfaces (Technology) -- Research -- Periodicals; 621.89
• DOI: 10.1002/ls.1258
• Languages: English
• ISSNs: 0954-0075

Abstract

Abstract: Effect of running‐in process on friction behaviour of carbon nitride (CNx) coating in N2 gas stream was investigated with a newly introduced two‐step ball‐on‐disk friction test, where the rubbed Si3 N4 ball in the pre‐sliding (step 1) was replaced by a new CNx‐coated Si3 N4 ball in the subsequent sliding stage under N2 gas (step 2). The two‐step friction test is clarified to be a simple but effective technique for obtaining contact material combination of self‐mated CNx coatings and for achieving stable and low frictions of CNx coatings. Friction coefficients of CNx/CNx in N2 gas stream decrease greatly from 0.07 without pre‐sliding to less than 0.025 in two‐step friction tests. The minimum friction coefficient of 0.004 was obtained by introducing 500 cycles of pre‐sliding in ambient air. These stable and low frictions are attributed to the generation of self‐mated CNx coatings and the formation of a lubricious layer on the disk surface. Copyright © 2014 John Wiley & Sons, Ltd.