Au-Cu-Ag系合金の時効硬化機構

抄録

We studied, by X-ray diffraction. the crystal structure of commercial Au-Cu-Ag alloys and the specimens electroplated with Au-Cu-Ag alloys (Table 1). aged at various temperatures in vacuum (10⁻⁴ mmHg) for 1 hr after solution treatment of the former and just after electroplating of the latter, and also measured the hardness of them by micro-Vickers hardness tester. In these experiments, there were tendencies that the maximum hardness of these aged alloys acquiring an ordered state were obtained at the aging temperature just under the ordering temperature ranges, while the alloys not proved to become ordered by such heat treatment had the maximum hardness before attractive increase of the precipitated phase. Thence it was inferred that the age-hardenability of these alloys was probably related to the ordering of these alloys in conjunction with the precipitation of new phase from the homogeneous solid solution (matrix).