Synergetic Lubricating Effect of WS₂ and Ti₃SiC₂ on Tribological Properties of Ni₃Al Matrix Composites at Elevated Temperatures

Abstract

The tribological behaviors of the Ni₃Al-WS₂-Ti₃SiC₂ composites and synergistic effect of composite solid lubricants are investigated from room temperature to 800°C. The results show that the Ni₃Al matrix composites (NASC) exhibit excellent tribological properties throughout the test temperatures compared to Ni₃Al-based alloy. The excellent tribological properties of NASC are attributed to the synergistic lubricating effect of WS₂ and Ti₃SiC₂. A lubricating film could be formed below 400°C, and an oxidation protection film is formed above 400°C on the worn surface of NASC during the sliding process, leading to low coefficients of friction (0.18–0.39) and wear rates (1.5–3.7 × 10⁻⁵ mm³N⁻¹m⁻¹).

KEY WORDS:

• Solid Lubrication Friction
• Self-Lubricating Composites
• Coupling Lubricants
• Wear Mechanisms

FUNDING

This work was supported by the Nature Science Foundation of Hubei Province (2012FFB05104); the National Natural Science Foundation of China (51275370); the Fundamental Research Funds for the Central Universities (2014-yb-004); the Project for Science and Technology Plan of Wuhan City (2013010501010139); the Academic Leader Program of Wuhan City (201150530146); and the Project for Teaching and Research project of Wuhan University of Technology (2012016).