Abstract
Ag-Nb(2)AlC composite materials with a Nb(2)AlC volume percentage ranging from 10% to 40% were prepared using the spark plasma sintering method. The composite with 10% Nb(2)AlC achieved a high density of 99.2%. The microhardness exhibited a peak value of 84.8 HV at a Nb(2)AlC content of 30%. The conductivity of the composite material decreases linearly with an increase in Nb(2)AlC content, ranging from 0.134 MS·cm(-1) to 0.086 MS·cm(-1). A three-dimensional laser scanning microscope was employed to characterize the morphology following arc erosion, and the erosion area was subsequently measured. Results indicated that arc erosion was concentrated on the Ag-20 vol.% Nb(2)AlC composite material, resulting in a smaller circular erosion area. As Nb(2)AlC content increased to 30% and 40%, the arc shifted, leading to an expansion of the erosion area. Notably, the Ag-30 vol.% Nb(2)AlC composite material exhibited the highest arc energy (3.401 kJ). The eroded surface displayed spattered particles and a convex morphology. Additionally, EDS and Raman spectroscopic analyses revealed the formation of Nb(2)O(5), Ag(2)O, and Al(2)O(3) on the surface. The arc erosion mechanism was analyzed from an electrical perspective, indicating that the formation of the arc is attributed to the development of a positive streamer and air breakdown within a strongly nonuniform field. Consequently, the surface atoms of Ag-Nb(2)AlC absorb energy, leading to the formation of metal ions that combine with the ionized air to create oxides. This research lays a theoretical foundation for the application of silver-based electrical contact materials.