ELECTRICAL CONTACT FOR USE IN A CIRCUIT BREAKER AND A METHOD OF MANUFACTURING THEREOF

摘要

An electrical contact for use in an electrical switching device is provided having low contact resistance, high wear resistance and high anti-weld characteristics. The contact includes a material composition of between 0.2 and 8 % by weight Gr, between 10 and 90 % by weight W and the remaining mixture consisting of Ag. The contact is manufactured using a process which yields a unique microstructure characterized by not having an interconnected Gr network around the Ag thereby providing a strong Ag to Ag bond. This process includes the steps of adding the appropriate amounts of Ag, W and Gr powder material together, blending together under low shear conditions to provide a homogeneous powder mixture while prohibiting the Gr from smearing onto the Ag, pressing the material mixture to form a contact, and then sintering and coining the contact.