- A salt which is applied via water slurry on silicon-aluminum clad aluminum surfaces.
- For use in nitrogen controlled atmosphere aluminum brazing oven.
- At brazing temperatures will break up tenacious aluminum surface oxides.
- Will promote the proper flow of clad aluminum alloy to make connection to other clad surfaces.
- At room temperatures the aluminum brazing flux is not water soluble.
- Can be used for the no-clean brazing of silicon-aluminum clad heat exchanger assemblies.
- Can also be provided as a dispensable flux paste or as a metal-loaded brazing paste.
Description: Superior No. 1250 is a floroalumiunate-based, inorganic type flux salt. The Superior No. 1250 fluxing ingredients are designed to activate at the high brazing temperatures of silicon-aluminum clad alloy in a nitrogen controlled atmosphere brazing oven. At brazing temperatures Superior No. 1250 will break up tenacious aluminum surface oxides and will promote the proper flow of clad aluminum alloy to make connection to other clad surfaces. The Superior No. 1250 is not a water soluble product.Applications: Superior No. 1250 brazing salts are typically applied by making a 15-30% water slurry (depending on flux concentrated needed) that are then sprayed on to the silicon-aluminum clad aluminum surfaces. Most controlled atmosphere silicon-aluminum clad furnaces will have a preliminary drying oven to remove the water carrier. The brazing oven works under near 100% nitrogen to heat the parts to 580-610°C to activate the flux which will break any surface oxides and promote the flow of the silicon-aluminum clad surface to bond to other clad aluminum surfaces. The assemblies made with this product are considered to be no-clean, meaning no additional cleaning is normally needed. In the event that customer requirements require removal of the un-reacted salts a simple power flush of the unit will remove the flux salts. Information provided by Superior Flux |