What type of filler metals are commonly used in silver brazing?

In silver brazing, the most commonly used filler metals are silver-copper and silver-zinc alloys. These alloys are engineered to create strong joints while offering desirable properties, such as good fluidity during the brazing process and strong bonding capabilities with the base materials. The presence of copper and zinc in these alloys helps enhance their melting points and improves their performance under various conditions.

Pure silver, while it can be used for brazing, is not typically favored as the sole filler metal due to its cost and the fact that it does not provide the same level of mechanical strength and thermal properties as the alloys. Moreover, copper-only fillers are unsuitable for silver brazing, as they do not have the silver content needed to form the appropriate bonds with the materials being joined. Aluminum fillers are also not appropriate for silver brazing, as aluminum requires different brazing techniques and filler compositions.

Therefore, silver-copper and silver-zinc alloys are the preferred choice in silver brazing due to their balanced properties that facilitate effective and reliable metal joining.