Fabrication and wear resistances of doped nano-SnO₂-Al₂O₃/Cu novel electrical contact composites

In order to meet the urgent needs of low-voltage electrical equipment for high quality electrical contact materials, and to protect the scarce resources and reduce the cost of electrical contact at the same time, doped nano-SnO₂-Al₂O₃/Cu novel electrical contact composites were fabricated by using powder metallurgy technique. The electrical conductivity, hardness and wear resistances of them were also investigated. The results show that both of re-sintering and cold deformation processes can improve the sintering quality, density, electrical conductivity as well as hardness of the composites significantly. With the increasing for total content of nano-Al₂O₃ and doped nano-SnO₂ particles, hardness and wear resistances of the doped nano-SnO₂-Al₂O₃/Cu electrical contact composites show the same change rule, which increases firstly and then decreases. When the total content of nano-Al₂O₃ and doped nano-SnO₂ particles is 0.80wt%, both of the hardness and wear resistances of the composites reach the optimum. While when the total content of nano-Al₂O₃ and doped nano-SnO₂ particles remains unchanged at 0.80wt%, with the content of nano-Al₂O₃ particles increasing, the hardness and wear resistances of the doped nano-SnO₂-Al₂O₃/Cu electrical contact composites enhance. When the content of doped nano-SnO₂ particles is 0, the wear resistance of the composite reaches the optimum. Therefore, compared with doped nano-SnO₂ particles, the nano-Al₂O₃ particles have a more significant improving effect on the wear resistance of the doped nano-SnO₂-Al₂O₃/Cu electrical contact composites.