BRAZE ALLOY STUDIES FOR REFRACTORY METAL SANDWICH STRUCTURES

This paper reviews studies to develop vacuum brazing procedures for fabricating D-36 (Cb-10% Ti-5% Zr) columbium and TZM (Mo-0. 5% Ti-0. 07% Zr) molybdenum honeycomb sandwich structures. Braze alloy flow temperatures ranged from 1800° to 3300° F. Higher remelt temperature braze alloy systems, as well as conventional brazing alloys, were investigated. The higher temperature remelt systems show promise but require additional development. Honeycomb sandwich panels which simulate application on an aerospace vehicle, either as hot monocoque structure or as modular heat shields for a double-walled structural concept, were fabricated for evaluation by structural and thermal testing.