The Effect of Sliding History on the Steady State Friction Coefficient between CNX Coatings under N2 Lubrication

Stable and super‐low friction of amorphous carbon nitride coatings in nitrogen gas by using two‐step ball‐on‐disk friction test

“…However, friction coefficients of CNx coatings in N 2 gas stream were greatly decreased with the introduction of pre‐sliding. Friction coefficient of CNx/CNx was reduced down to a value of less than 0.05 in the steady stage when N 2 gas was blown to the sliding interface after 1000 cycles of pre‐sliding in ambient air . In case of the two‐step friction test, when 1000 cycles of pre‐sliding was given in step 1 using a Si 3 N 4 ball, the friction coefficient of CNx/CNx in step 2 decreased shortly to a steady stage together with a stable and low value of less than 0.01.…”

“…Two‐step friction test has been clarified to be a promising technique for obtaining stable and low frictions of CNx coatings in N 2 gas stream. According to the previous research, the steady‐state friction coefficients under N 2 gas stream are greatly affected by the pre‐sliding process, especially the pre‐sliding cycles and gas atmospheres . Hence, the effects of pre‐sliding cycles (0–1000) and gas atmospheres (N 2 , O 2 and ambient air) in step 1 on the friction behaviour of CNx/CNx in N 2 gas stream (step 2) were systematically investigated, and typical results are presented in Figures and , respectively.…”

“…The beneficial effect of N 2 gas on reducing frictions of CNx coatings is improved by running-in process, which is pre-sliding before introducing N 2 gas to the sliding interface. [6][7][8] Specifically, a quick reduction of the steady-state friction coefficient from 0.1 to 0.02 is observed in the sliding contact of Si 3 N 4 ball/CNx-coated Si 3 N 4 disk by blowing N 2 gas at the 1000th cycle after pre-sliding in air. Such effect is much more pronounced when the pre-sliding is conducted in O 2 gas for the initial 50 cycles, the steady-state friction coefficient in the subsequent N 2 gas environment decreases drastically to 0.005 in the sliding contact of CNx-coated Si 3 N 4 ball/CNx-coated Si 3 N 4 disk.…”

“…The beneficial effect of N 2 gas on reducing frictions of CNx coatings is improved by running‐in process, which is pre‐sliding before introducing N 2 gas to the sliding interface . Specifically, a quick reduction of the steady‐state friction coefficient from 0.1 to 0.02 is observed in the sliding contact of Si 3 N 4 ball/CNx‐coated Si 3 N 4 disk by blowing N 2 gas at the 1000th cycle after pre‐sliding in air.…”

Lubricity of carbon nitride coatings in humid nitrogen gas environment

“…Amorphous Carbon Nitride: a-CN X CN X Adachi and Kato, 2008 Si 3 N 4 CN X 0.01 , Adachi, et al, 2005b Luo, et al, …”