抄録
Alloys of β phase of the Cu-Sb system were quenched and tempered and the changes in their structure were examined by means of microscopic, differential dilatometric, and X-ray analyses. The following conclusions were drawn: (1) The number of atoms in the unit cell of β phase is 14 in the atomic ratio of 10 Cu and 4 Sb. (2) By rapid cooling of β phase an intermediate phase β's formed which precipitates on tempering, at first, δ phase (expansion) then θ phase (contraction) and finally decomposes into δ and θ phases at 280_??_300°. (3) This change β'→δ+θ also appears in cast specimens. (4) Alloys of 55.5_??_63.5% Cu quenched from β field have a facecentered tetragonal lattice with a=5.66_??_5.89Å, c=5.94_??_6.08Å, c/a=1.007_??_1.07, but those of 63.5_??_68% Cu have a cubic lattice with a=5.91_??_5.928Å or, by tempering, a face-centered tetragonal lattice with a=5.94_??_5.97Å, c=5.80_??_5.88Å, c/a=0.972_??_0.990. (5) The cubic lattice of the β' phase interchanges the axes of a and c at about the eutectoid composition (63.5%Cu). (6) By ageing of quenched β alloys, the ratio of c/a increases in alloys rich in θ phase, but decreases in alloys rich in δ phase.
