Method for direct application of flux to a brazing surface

Abstract

A method is disclosed for direct application of a brazing flux material to a brazing surface. The method includes the step of applying a brazing filler material to a substrate utilizing a kinetic spray process to form a brazing surface. Following application of the brazing filler material to the substrate brazing flux material can be directly applied to the brazing surface as either a dry powder or a wet slurry. The nature of the brazing surface allows the applied flux material to adhere to the surface without the utilization of additional binders or resin materials.

1 . A method for application of a brazing flux material to a brazing surface comprising the steps of: 
 a) providing a brazing filler material as a particle mixture wherein the average nominal particle size of the particle mixture is from 65 to 200 microns, entraining the particle mixture into a flow of a gas, the gas at a temperature insufficient to cause thermal softening of the particle mixture, directing the particle mixture entrained in the flow of gas through a supersonic nozzle placed opposite a substrate, and accelerating the particle mixture to a velocity of from 300 to 1200 meters per second to result in adherence of the particle mixture onto the substrate thereby forming the brazing surface by a kinetic spray application;    b) depositing a brazing flux material directly onto the formed brazing surface.    
   
   
       2 . (canceled)  
   
   
       3 . The method of  claim 1 , comprising providing the gas at a temperature of from 300 to 3000 degrees Fahrenheit.  
   
   
       4 . The method of  claim 1 , wherein the brazing flux is deposited in at least one of the following ways: dry static powder, as a sifted dry powder, by dry powder brush application, as a dry powder smear, by running a wheel containing flux over the brazing surface, as a wet slurry by dip application, as a wet slurry by spraying application, or a mixture thereof.  
   
   
       5 . The method of  claim 1 , further comprising depositing from 2 to 40 grams per meter squared of brazing flux material directly onto the brazing surface.