Metallurgical aspects of palladium-silver porcelain-bonding alloys

Metallurgical aspects of five commercial Pd-Ag porcelain-bonding alloys have been investigated using X-ray diffraction, light microscopy and X-ray microanalysis. All alloys are mainly single-phase systems, but they appear to be inhomogeneous due to constitutional supercooling. Porcelain firing times are presumably insufficient to reach homogeneity. Two alloys show a virtually identical chemical composition but a differing amount of segregation which should be attributed to minor components controlling the solid diffusion process. Both indium-containing alloys show signs of a minor second phase which could not be identified due to its finely dispersed character.