1987 Volume 5 Issue 1 Pages 54-59
The roles of elements in the insert metal of 80%copper-20%Haynes No. 188 for bonding of Si3N4 to tungsten and molybdenum have been investigated. EDX analysis of the interlayer of joints revealed that chromium was concentrated in the region adjacent to Si3N4 and copper was concentrated in the center region of the insert layer.
CrSi2, Cr2N and CrN were found in the region adjacent to Si3N4. As the results of bonding of Si3N4 to tungsten using insert metals of copper base ternary and binary alloys containing iron, nickel, chromium or cobalt, good strength of joints were obtained only when chromium was contained in the insert metal. These results suggest that chromium is the main element to contribute to bonding of the insert metal to Si3N4 by forming chromium silicide or nitride at the interface and copper which enriched in the center region had the function to relieve the thermal stress by forming buffer layer in the insert layer.
