Description
In the last years efforts were made to replace traditional Pb-Sn solders by more environmentally friendly alloys. The present investigation of the systems Ag-Ni and Ag-Ni-Sn is part of the research carried out. It is also a contribution to COST Action 531. Both systems are constituents of the quaternary Ag-Cu-Ni-Sn system, which is one of the key systems for the description of interactions between widespread Ag-Cu-Sn solder and a Ni containing substrate. The binary system Ag-Ni is dominated by a large miscibility gap which is estimated to extend up to 3500 ż 4000 K. Enthalpies of mixing in the liquid state were measured at 1500 °C. Subsequently a new version of this system was established on the basis of DSC measurements and calculations including the results from the calorimetric experiments. For the Ag-Ni-Sn system information in the available literature is very scarce. The work presented here comprised the investigation of more than 120 samples by XRD, DTA and EPMA. No ternary compound has been found until now and ternary solubilities are either small or even negligible. Nevertheless this system was found to be rather complex and experimentally challenging, because of the wide extension of the miscibility gap from the binary Ag-Ni system into the ternary. Furthermore the existence of incommensurate Ni-Sn phases and their related transitions increased the complexity of the phase relations. Five isothermal sections at 200, 450, 700, 950 and 1050 °C as well as a liquidus projection and the Scheil diagram are presented. Calorimetric measurements in this system were performed to determine enthalpies of mixing at 1000, 1220 and 1400 °C. In addition the liquid miscibility limit in the ternary could be estimated from these measurements.| Period | 2006 |
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| Event title | Nicht angegeben |
| Event type | Other |
| Location | UnknownShow on map |