An alloy sold under the tradename of Ticusil by the Wesgo Division of GTE Products Corporation, Belmont, Calif. contains 4.5% by weight of titanium, 68.8% by weight of silver and 26.7% by weight of copper. This alloy, while having the ability to wet various ceramic materials and has a relatively low brazing temperature, and upon brazing contains a brittle dispersed phase.
Other titanium containing alloys containing higher amounts titanium are known to wet ceramics but they are brittle. These can be made into a flexible foil form by rapid solidification techniques, however, upon brazing it will form a brittle alloy joint.
When brazing brittle ceramic to metal components with different coefficients of thermal expansion, the reliability of brazed joint is highly dependent on the brazing alloy ductility, because the ductile alloy will minimize the stress between two different materials. Brittle alloys when used for brazing brittle notch sensitive ceramic to metal result in the ceramic almost always failing after being exposed to a relatively few thermal cycles.