Improving mechanical and electrical contact performance of silver based electrical contact material reinforced by flower spherical zinc oxide loaded with silver nanoparticles

Flower spherical ZnO loaded with Ag nanoparticles was synthesized by hydrothermal method. Ag/ZnO electrical contact materials were prepared by powder metallurgy combined with hot extrusion technique. During the hydrothermal reaction, Ag nanoparticles entered the interlayer gaps of flower spherical ZnO and uniformly deposited on its surface. The tensile mechanical test results indicate that the Ag/ZnO electrical contact materials prepared by ZnO, Ag@ZnO (75 wt%) and Ag@ZnO (50 wt%) exhibited elongations of 6.8 %, 13.8 % and 12.1 %, respectively. This result indicates that appropriate loading of Ag nanoparticles on flower spherical ZnO could significantly improve the mechanical properties of Ag/ZnO electrical contact materials. The contact resistance of electrical contact materials significantly affects their temperature rise characteristics. During 20, 000 cycles process, Ag/ZnO electrical contact material prepared by Ag@ZnO (50 wt%) exhibited the lowest temperature rise of 6.33 K under the conditions of DC 36 V/10 A. Considering both mechanical and electrical contact performance, Ag/ZnO electrical contact materials prepared by Ag@ZnO (50 wt%) exhibited the optimum overall performance.