溶融銅-ヒ素, 銅-インジウム系合金の活量について

溶融銅合金に関する熱力学的研究 (第4報)

抄録

Activities of copper and indium in liquid Cu-As and Cu-In alloys have been measured by means of the galvanic cell:
(-) Cu (s or l) |Cu⁺, (KCl-NaCl) |Cu-As (l)(+)
(-) In (l) |In⁺, (KCl-NaCl) |Cu-In (l)(+)
Owing to the high vapor pressure of arsenic, the measurements for the copper-arsenic system were limited in the range up to NAs=0.305. The electromotive forces of the cell at temperatures below the melting point of copper were corrected with the term expressed by the function of free energies of fusion of copper at experimental temperatures. Activities of arsenic were determined by integrating the values ofαfunction calculated from acu.As the lower limit of the integration, it is used the activity of arsenic at NAs=0.27 obtained by meams of the transportation method. Activity of arsenic thus obtained shows a considerable negative deviation from Raoult's law, andγ^o_As at 1, 000°C is estimated as low as 1.45·10-4.
Measurements for the copper-indium system were made in the ranges 0.201 to 0.799 in NIn and 700°to 1, 000°C. Deviations of the activities of copper and indium from the ideality are positive for the indium rich side and are negative in the copper rich region of the system. The value ofγ^o_In is estimated 0.27 at 1, 000°C.