Contact material based on copper and chromium (CuCr) is widely used for vacuum interrupters (VIs) and has found worldwide acceptance in medium-voltage applications, especially for high-current interruption. Contact material with a weight content of chromium between 25 and 60 wt.% is almost exclusively used. A new contact material was established based on a multilayer system to improve the interruption ability and mechanical properties and reduce the contact resistance. After a combined sintering and melting process in a high-vacuum furnace, a material of high density and low gas content is produced. The finished blank consists of the following layers: CuCr-sheathing, copper bulk material, and a stainless-steel support resulting from the lost mold. It turned out that the higher thermal and electrical conductivity as well as mechanical properties of the multilayer contact material improved the interruption ability of the VI. Investigations of switching behaviors were carried out in standard VIs. Additionally, the standard chromium content of 25 wt.% in CuCr and the influence of higher chromium content was investigated with respect to interruption ability. Afterwards, the microstructure on the contact surface was analyzed with scanning electron microscopy and energy dispersive X-ray.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.