Microstructure and Mechanical Properties of a Cu-Pd-Ag Alloy Wire with Aging Treatment

Abstract:

Cu-Pd-Ag alloy is widely used in electronic device applications due to its relatively low electric resistance. To obtain higher strength wire, age-hardening is usually conducted to this alloy wire. However, the detailed hardening mechanism of Cu-Pd-Ag alloy was not clarified enough. In the present paper, we investigated the microstructure and hardness of the Cu-Pd-Ag alloy wire with aging treatment. Original alloy contained many rods with an Ag-rich α phase extended along the wire direction in a Cu-rich α phase matrix. After heat treatment of 623K with 1 hour, the matrix was transformed to the β phase contained many elongated α₂ phases as nanolamellar structure. Many β’ phase precipitated in the rods. Hardness measured with nanoindentation test showed that the matrix had a higher value than that of the rods. In the Cu-Pd-Ag alloy wire, the nanolamellar structure of the matrix was revealed to contribute to the hardening of the wire.

• Periodical: Materials Science Forum (Volume 941)
• Pages: 1167-1172
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.941.1167
• Online since: December 2018
• Authors: Chihiro Iwamoto*, Fumio Watanabe, Risei Koitabashi
• Keywords: Electrode Materials, Pd Alloy, Scanning Transmission Electron Microscopy, Wire Drawing

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