Excellent anti-arc erosion performance and corresponding mechanisms of a nickel-belt-reinforced silver-based electrical contact material

Abstract Three-dimensional (3D) continuous Ni-network-reinforced Ag-matrix composite materials were prepared by hot-pressing Ag–Ni composite powders with Ni powders coated on the surface of Ag granules. The formation of a 3D continuous Ni network enhances the load transferred from the Ag matrix to the second-phase Ni, inducing the co-deformation of Ag and Ni during the drawing deformation. The co-deformation begins as orientation rotation and refinement; e.g. the Ag matrix slips on {111}〈1 1 - 0〉, twins on {111}〈11 2 - 〉, and 〈100〉 drawing texture are formed in second-phase Ni along the drawing direction. Finally, the 3D continuous Ni networks were torn and drawn into belts that are parallel to the axial direction of the composite wire. Increasing the real strain could increase the length of the Ni belts in the axial direction, thus increasing the hardness and electrical conductivity of Ag–Ni electrical contact materials. Additionally, the two-dimensional characteristics of the belts with high profile drag increase the flow resistance of molten Ag. Therefore, the belt-reinforced Ag–Ni electrical contact materials show a low mass loss after 100000 times of contact (1.8 mg, only 22.8% of that of the round fibres reinforced sample).