熱処理過程で陽極組織内に発生する相変化Cu₂O→CuO+Cu°について

銅陽極不働態化の研究 (第9報)

抄録

A certain heat treatment (annealed at 1, 000°C, followed by slow cooling) was employed to various kinds of commercial copper anodes in an attempt to increase their dissolution activity in a copper electrorefining electrolyte.
It has been observed that such heat treatment brings about a drastic change in the microstructure as well as a substantial disappearance of Cu₂O phase from the grain boundaries. Both electrochemical and X-ray diffraction analyses have confirmed that a phase conversion Cu₂O=CuO+Cu° surely occurs in the matrix of copper anode so heat treated.
The results of dissolution experiments also appear to indicate that;
1) The heat treatment results in a great enhancement in the dissolution activity of copper anodes to such an extent that it can hardly be passivated under conventional Cu ER conditions, and
2) The sole employment of annealing (with no subsequent slow cooling) increases the dissolution activity but a little.