Observation of Thermophysical and Tribological Properties of CNT Reinforced Si₃N₄

Abstract

Thermophysical and tribological measurements have been performed on carbon nanotube added silicon nitride composites. Higher thermal conductivity values were observed in the case of the sample with CNT than for the reference sample. As was observed from tribological measurements, nanocomposite Si3N4 without carbon nanotubes shows a higher friction coefficient than carbon nanotube - Si3N4. The results of wear study indicate that the Si3N4 ball (used as static partner) was more damaged with MWCNTs addition nanocomposite than with pure Si3N4 ceramic. A pronounced difference was observed in the wear rate: there was a much higher wear for carbon nanotube - Si3N4 than for Si3N4 without MWCNTs.

Enhanced Tribological Performance of Silicon Nitride-Based Materials by Adding Carbon Nanotubes

“…In these composites, the addition of CNTs usually led to the reduction of friction and wear rate compared with monolithic Al 2 O 3 , but results were greatly dependent on the presence of CNTs agglomerates 8,9 . Just one work reports about the tribological properties of Si 3 N 4 /CNTs composites at low loads obtained by dry ball‐on‐plate tests 12 . Results showed a slight decrease in friction for composites containing 3 wt% of CNTs, whereas the wear rate increased one order of magnitude due to the presence of CNTs agglomerates.…”

Silicon Nitride-Based Composites with the Addition of CNTs—A Review of Recent Progress, Challenges, and Future Prospects

“…According to Miranzo et al [97], β phase content has a positive effect in enhancing the thermal conductivity. To our understanding, the enhancement of thermal conductivity of the composite claimed by Koszor et al [91] was likely due to the presence of β phase, not of the CNTs.…”

“…Figures 12 and 13 illustrate the influence of CNT addition on wear rate and the coefficient of friction during the tribological tests of CNT-reinforced silicon nitrides tested up to now. Koszor et al reported that the friction coefficient decreased with the addition of 3 wt.% MWCNTs in Si 3 N 4 composite [91]. The wear rate of monolithic silicon nitride composite was reported to be 3.02 × 10 −6 mm 3 /N•m and the addition of 3 wt.% MWCNTs reduced the wear to 3.34 × 10 −5 mm 3 /N•m [91].…”

“…Koszor et al reported that the friction coefficient decreased with the addition of 3 wt.% MWCNTs in Si 3 N 4 composite [91]. The wear rate of monolithic silicon nitride composite was reported to be 3.02 × 10 −6 mm 3 /N•m and the addition of 3 wt.% MWCNTs reduced the wear to 3.34 × 10 −5 mm 3 /N•m [91].…”

“…Tribological properties of carbon based nanostructured reinforced Si 3 N 4 composites have been widely investigated during the last decade [24,51,68,[76][77][78][79][80][81][82][83][91][92][93][94].…”