摘要 |
A process for making metal joining paste, particularly suitable for precision soldering and brazing, which comprises preparing a paste vehicle by mixing together, at an elevated temperature, paste ingredients including solvent, flux and specialized additives, cooling said vehicle, and blending metal powder therewith. Blending preferably is subsequent to cooling, but can be simultaneous with cooling, though without significant exposure of the metal to the vehicle at elevated temperature. Cooling of the vehicle takes place under shock cooling conditions, such as to obtain a fine particle size suspension, and is to a final temperature inhibitive of significant reaction of metal powder with vehicle acidic constituents. The present invention provides increased viscosity control and suspension stability necessary for fine bore automatic dispensing of the paste.
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