Diffusion Bonding of AgC–Cu Bi-layered Electrical Contacts

  • Daudi R. WaryobaEmail author
  • Linsea Paradis
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


Due to the immiscibility of graphite in copper and silver, the conventional press and sinter method for fabrication of bi-layered silver graphite-copper electrical contacts are a challenging process. During sintering of silver graphite-copper compacts, silver diffuses into copper leaving a trace of graphite at the interface. This creates a poor interface between the mating surfaces, thereby decreasing the shear strength of the joint. In this work, interlayers with different compositions were used to promote diffusion bonding at various sintering conditions. The results show that vacuum diffusion bonding using an interlayer of Ag–Cu, with eutectic composition, is an effective method for fabricating the AgC–Cu bilayer electrical contacts.


Diffusion bonding Sintering Electrical contacts EDS 



This work was partly funded by the Powder Metal Initiative (PMI) through the Pennsylvania Department of Community and Economic Development (DCED), grant #C000063072, and by the Engineering Technology and Commonwealth Engineering (ETCE), Pennsylvania State University. Conventional sintering by Symmco Inc. and Contact Technologies Inc. is also gratefully acknowledged.


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© The Minerals, Metals & Materials Society 2020

Authors and Affiliations

  1. 1.Engineering, Applied MaterialsPenn State DuBoisDuboisUSA

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