THE TERNARY GA-PD-SB PHASE-DIAGRAM - A SYSTEM RELEVANT TO CONTACT MATERIALS FOR GASB

The phase relationships of GaSb in the ternary system Ga-Pd-Sb were st udied for an isothermal section at 500 degrees C by means of X-ray dif fraction (XRD) and electron probe micro analyses (EPMA). Eight invaria nt ternary phase reactions, i.e. three quasibinary eutectic reactions, three ternary transition reactions and two ternary eutectics were ide ntified by means of differential thermal analyses (DTA). All experimen tal phase diagram informations were combined to construct a complete r eaction scheme (Scheil diagram) in the investigated composition area a nd the liquidus surface was derived based on the results of the DTA me asurements. The gallium-rich part of the limiting binary Ga-Pd system was reinvestigated by means of DTA and XRD.