2017 Volume 58 Issue 1 Pages 11-15
A Cu-Ni alloy in which the nickel content was included up to approximately 5 mass% was melted in a graphite crucible with a high frequency induction furnace to prepare the Cu-Ni-Csat (saturated carbon) alloy. Solubility of carbon into Cu-Ni alloy increased with the nickel content and with the melting temperature. The relation between the activity coefficient of carbon for Cu-Ni-Csat and the temperature could be expressed by numerical formulas. This work proposed that the interaction parameter, ωNiC, for Cu-Ni-Csat was −16.1. The precipitated particles from the melt were graphite. Vickers hardness of Cu-Ni-Csat system increased with C content. The Cu-Ni-Csat alloy prepared in this study was hardened by precipitation hardening of the graphite particles and solution hardening of Ni.