Effect of multiwalled carbon nanotubes on the lubricating properties of TiAl–Ag composites based on the changes in applied loads and testing temperatures

Abstract

The rapid development of self-lubricating materials has been driven by the urgent demands of aerospace and automobile industries. In this paper, the effect of multiwalled carbon nanotubes (MWCNTs) on the lubricating properties of TiAl–Ag self-lubricating composites is studied based on the changes in applied loads and testing temperatures. The results show that the TiAl substrate composite containing 4.0 wt% Ag and 1.7 wt% MWCNTs (TAC) obtains a small mean friction coefficient of 0.21 and a low mean wear rate of 2.14 × 10⁻⁴ mm³ N⁻¹ m⁻¹ at 13 N–450 °C. It could be concluded that the lubricating film formed at 13 N–450 °C contains massive Ag and MWCNTs with 50–200 GPa in tensile strength, leading to the improvement of the tensile strength of the lubricating film. The improvement of the tensile strength of the lubricating film is beneficial for acquiring the excellent friction and wear behavior of TAC at 13 N–450 °C. Because of its excellent tribological performance, TAC can be chosen as the promising structural material for mechanical components.