Arc erosion resistance of hybrid copper matrix composites reinforced with CNTs and micro-TiB2 particles

Abstract

Synergistic strengthening is increasingly explored for developing high-performance copper matrix composite. In this work, the hybrid copper matrix composites reinforced with carbon nanotubes (CNTs) and micro- TiB2 particles（（CNTs-TiB2）/Cu composites）were prepared by electroless copper plating, powder metallurgy and hot extrusion. The arc erosion resistance of the hybrid copper matrix composites was studied in JF04C electrical contact testing system. And the synergistic effect of CNTs and TiB2 particles in different content ratios on the arc erosion resistance of composites was analyzed emphatically. The action mechanism of CNTs and TiB2 particles in arc erosion process is discussed in detail. Results show that the arc duration and arc energy of the hybrid copper matrix composites are lower than that of copper matrix composites single reinforced with CNTs or TiB2 particles. When the volume fraction of CNTs is 4.2% (The content of TiB2 particles is 1.6%), the arc erosion resistance of the hybrid copper matrix composites is optimal. In arc erosion process, CNTs can form a network structure parallel to the extrusion direction in copper matrix, and the continuous CNTs network structure can effectively disperse cathode arc, promote arc movement, increase work function of copper matrix composites, inhibit electron emission and reduce total emission current density. And the micro- TiB2 particles are helpful to improve the viscosity of molten pool, which can reduce the material mass loss and erosion pit on the surface of composites. Under the combined actions of CNTs and TiB2 particles (4.2CNTs-1.6TiB2)/Cu composite presents better arc erosion resistance stability, lower arc duration and energy.