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The production of ultrahigh-purity copper for advanced applications


Ultrahigh-purity copper (UHPC) of five to seven nines has been developed, and commercial production has been started by Nippon Mining and Metals Company. This value-added copper has such characteristics as high electrical and thermal conductivity at very low temperatures, low softening temperatures, and high workability due to fewer nonmetallic inclusions and voids as compared with conventional high-purity copper (i.e., four nines). Taking advantages of these characteristics, UHPC is being applied to bonding wire of integrated circuits and cables for audio devices.

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Correspondence to Masanori Kato B.S..

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Kato, M. The production of ultrahigh-purity copper for advanced applications. JOM 47, 44–46 (1995). https://doi.org/10.1007/BF03221340

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  • Nonmetallic Inclusion
  • Copper Foil
  • Audio Device
  • High Softening Temperature
  • Bend Fatigue Strength