Preparation of silver-coated transition metal selenides and properties of silver-based composites

To improve the interface bonding strength between the substrate and phases in the Ag-based composite, the silver-coated NbSe₂ and silver-coated Ti_0.09Nb_0.91Se₂ particles were synthesized by chemical reduction method, and the Ag-based composites were prepared by powder metallurgy. The results show that, the silver particles are uniformly distributed on the surface of the transition metal selenides, and the Ti_0.09Nb_0.91Se₂ particles show the better coating effect. After covering the Ag coating, the contact between the transition metal selenides and the metal matrix silver is increased, leading to the better wettability and the smaller repulsive force between Ag and the transition metal selenide. Moreover, the possibility of the transition metal selenide decomposition in the Ag-based composite materials is greatly reduced after the Ag coating. The densification of the Ag-based composite materials is improved and the interface bonding strength between the Ag substrates and the transition metal selenides is enhanced. Compared with the Ag-based composites with the uncoated NbSe₂, the friction properties of the Ag-based composites containing the silver-coated transition metal selenides decrease slightly.