Study of Tribological Properties of MoS<sub>2</sub>/Cu-Fe Matrix Self-Lubricating Composites Prepared by Induction Sintering at Elevated Temperature

Abstract

The molybdenum disulfide(MoS2)/copper(Cu)-ferrum(Fe) matrix self-lubricating composites with various amounts of MoS2 additives were prepared by induction heating sintering method combined with the alloying of the Cu-Fe matrix with various metallic elements. As the temperature was increased from room temperature to 800°C, the mechanical and tribological properties of the composites were measured using the universal testing machine and MRH-3 friction-wear tester. The phase compositions and worn surface morphologies of the composites were analyzed by means of X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). Meanwhile, wear mechanisms were discussed. It was found that the mechanical and friction/wear properties of MoS2/Cu-Fe matrix self-lubricating composites were related to the induction frequencies and the contents of the MoS2 as the solid lubricant. The increased MoS2 content resulted in increased mechanical and friction/wear properties at first and then decreased subsequently. The composites with proper MoS2 contents and induction frequencies have the lower the friction coefficients and wear rate at room temperature to 800°C. Meanwhile, the self-lubricating films were mainly made up of some compositions, such as pearlite, cementite, sulphide, solid solution alloy of Mo and Fe, molybdenum oxide in elevated temperature; the wear mechanism of composites has been changed from abrasive wear to ploughing wear.