Silver Braze 72a

Silver Braze 72a is a lithium modified version of Silver Braze 72. The lithium content facilitates the wetting of stainless and refractory metals when used in a hydrogen or inert atmosphere of low dew point (-70F/-55C or direr). The use of endo-gas or exo-gas atmospheres, or standard fluxes, is not recommended since they react with the lithium and interfere with bonding. A minimum brazing temperature of 50F (10C) above the flow point is suggested for atmosphere furnace brazing. It is particularly adaptable to brazing thin sections of stainless steels because solution of the base metal by the filler metal is negligible.

The properties of a brazed joint are dependent upon numerous factors including base metal properties, joint design, metallurgical interaction between the base metal and the filler metal. Joints brazed with Silver Braze 72a have been used for applications where operating temperatures where operating temperatures were intermittently as high as 900F (480C). When continuous elevated temperature exposure to oxidizing conditions is to be expecting (1000 hours or more), the maximum operating temperature should be reduced to 500F (260C). Joints made on heat resistant alloys with these filler metals are much more resistant to interface corrosion than flux brazed joints. Final acceptance should be based on tests made under the anticipated service conditions.