In the high-stakes world of energy transmission, even the smallest component can make a big difference. Enter the humble spring contact finger, a critical part of Gas Insulated Lines (GIL) that connect and transmit electrical power. Over time, these fingers can shift due to vibrations, leading to friction, wear, and increased contact resistance. This not only hampers power transmission but also generates metal debris that can cause partial discharges, potentially leading to insulation breakdown and catastrophic equipment failure.
Enter Jiahao Yan, a researcher from the School of Electrical Engineering at Xi’an University of Technology in China, who has been tackling this issue head-on. Yan and his team have developed a innovative solution: incorporating graphene into the existing silver-plated layer of the contact finger. “The idea was to enhance wear resistance and optimize overall performance,” Yan explains. “Graphene’s exceptional mechanical and electrical properties make it an ideal candidate for this application.”
The team used a cyanide-free silver-plating technique based on a thiosulfate system to fabricate a silver/graphene composite coating. By varying the coating thickness and graphene content, they were able to optimize the coating’s performance. “We found that at a cathodic current density of 0.4–0.6 A dm^−2, the coating surface was smooth, graphene was uniformly distributed, and adhesion was strong,” Yan says.
The optimal coating parameters, as identified by performance evaluation using radar charts, were a thickness of 10 μm with 8.23% graphene content. This configuration maintained a stable friction coefficient around 1, reduced contact resistance by approximately 100 μΩ compared to pure silver, increased hardness by 7.08 HV, and preserved thermal conductivity and corrosion resistance.
The implications of this research are significant for the energy sector. By enhancing wear resistance and reducing contact resistance, this new coating can improve the efficiency and longevity of GIL equipment, leading to more reliable power transmission and reduced maintenance costs. “This could potentially revolutionize the way we approach GIL maintenance and design,” Yan suggests.
The study, published in the journal Materials Research Express, opens up new avenues for research and development in the field. Future work could focus on scaling up the production of these composite coatings and exploring their application in other high-wear, high-conductivity scenarios. As the energy sector continues to evolve, innovations like this will be crucial in ensuring the reliable and efficient transmission of power.
