Preparation and tribological behaviour of laminated Ti₃AlC₂ crystals as additive in base oil

Abstract

Laminated ternary compound Ti₃AlC₂ crystals were synthesised by pressureless sintering the mixture powders of 3Ti/1·1Al/1·8C, 3Ti/1Al/1·8C/0·2Sn, 1Ti/1·8TiC/1Al and 1Ti1·8TiC1Al0·1Sn at 1400°C with preliminary liquid magnetic stirring mixing. The X-ray diffraction results indicate that Ti₃AlC₂ prepared from 3Ti/1Al/1·8C/0·2Sn has the highest purity, and the addition of appropriate Sn favours the synthesis of high purity Ti₃AlC₂. Scanning electron microscopy images show that Ti₃AlC₂ samples exhibit lamellar-like microstructure with thickness of ∼100 nm. The tribological properties of Ti₃AlC₂ as an additive in 100SN base oil were evaluated with a ball on disc tester. The results show that the Ti₃AlC₂ additives exhibited good friction reduction and wear resistance at 5 wt-% concentration. Under determinate conditions, the base oil containing 5 wt-% Ti₃AlC₂ samples presented good tribology performance under the load of 15 N. The improved tribological properties of the Ti₃AlC₂ samples could be attributed to the formation of tribofilm in friction process.

Keywords:

• Ti₃AlC₂
• Layered carbide
• Synthesis
• Tribological behaviour
• Tribofilm

Acknowledgements

This work was supported by the National Natural Science Foundation of China (grant nos. 51275213 and 51302112), Jiangsu National Nature Science Foundation (grant no. BK2011534) and Scientific and Technological Innovation Plan of Jiangsu Province in China (grant nos. CXLX12_0636).