A number of alloys have been examined microscopically. From these observations, from the equilibrium diagrams of the component binary systems, and from the application of the phase rule, a room temperature isothermal section has been deduced. Three vertical sections through the ternary system have been partially constructed from differential thermal analysis. These data show that invariant planes occur at 143, 148, 241, and 506 °C. From the information obtained from the vertical sections and the room temperature isothermal section, isothermal sections have also been proposed at 143 and 148°. The transformation at the 143 °C invariant plane is a ternary eutectic, at 148° a ternary peritectic, and the other transformations at 241 and 506° are also ternary peritectics.Some evidence indicates that the ξ-phase of Ag–Al system and the γ-phase of Ag–In system link up through the ternary system forming a single phase region, and that such may also be the case with the phases µ and α′ of the systems Ag–Al and Ag–In, respectively. The phases ε and [Formula: see text] of the system Ag–In do not appear to be capable of dissolving aluminum appreciably.
THE ROOM TEMPERATURE SECTION OF THE PHASE EQUI-LIBRIUM DIAGRAM OF THE Al-Cr-Cu TERNARY SYSTEM