Scientists use copper-silicon carbide nanocomposite to modify resistant-welding electrodes

Iranian researchers in association with Materials and Energy Research Center (MERC) and Pohang University of Sciences and Technology, South Korea, used nanotechnology and produced copper-silicon carbide nanocomposite applied in resistant-welding electrode. This nanocomposite shows very high strength and thermal stability in comparison with usual electrodes used in industries. It is highly cost-effective because cheap materials have been used in its production. The researchers firstly produced nanocrystalline copper powder with homogenous distribution of silicon carbide through high-energy mechanical milling method, and they investigated the structure of the product. Next, they produced bulk samples of the nanocomposite by using nanocrystalline powder through hot pressure method. Finally, the microstructure of the produced nanocomposite was characterized. In addition, the researchers studied mechanical properties and electrical conduction of the nanocomposite at room temperature and higher temperatures to investigate the performance of the nanocomposite at working conditions of resistant-welding electrodes. Almost homogenous distribution of SiC nanoparticles, thermal stability, and small size of copper particles in the presence of nanoparticles are among the important achievements of the research, which were obtained through the synthesis process. In addition, results obtained from the measurement of pressure and microhardness properties at environment temperature showed that as the structure of particles becomes smaller in size and as nanoparticles are added up to four volume percent, significant increase is observed in the strength up to five times and three times in hardness in comparison to copper particles at micrometric scale. The nanocomposite can be used in the production of welding electrodes that are placed in the top of resistant-welding devices. Resistant welding has applications in the attachment of plates in the body of automobile, home appliances and building productions. Results of the research have been published in Ceramics International, vol. 40, January 2014, pp. 951-960.