Oxidation Behavior of Silver‐ and Copper‐Based Brazing Filler Metals for Silicon Nitride/Metal Joints

Abstract

The oxidation behavior of reactive‐element‐containing brazing filler metals at 600°C was studied. Weight‐gain measurements coupled with scanning electron microscopy and energy dispersive X‐ray analysis indicated the formation of a nonprotective oxide on the following three ternary alloys: (i) Cu‐80%, Sn‐10%, Ti‐10%; (ii) Ag–Cu eutectic + 5% Ti; and (iii) Ag–Cu eutectic + 5% Zr. Additions of Ni and Si to these alloys failed to reduce spallation. However, a protective oxide was formed by adding Al. The resultant quaternary alloys possessed excellent flow properties on silicon nitride.