Nowadays, due to the search for more efficient and steady processes of aluminum combination and the products that cannot be manufactured using flux, the issue of application of flux-free soldering methods for aluminum-based alloys is highly relevant. The lack of the description of the processes and mechanisms of flux-free soldering by the technique of friction of the solder on the aluminum surface makes it urgent to study and describe them in detail. To carry out the study, the authors produced zinc-based alloys and prepared solder rods using the hot pressing method. Using the technique of friction of a rod against the surface of the heated aluminum substrate, the authors identified minimum temperatures of the setting of zinc solders of different compositions with aluminum surfaces. The experiment proves that these temperatures correlate with the liquidus temperatures of these alloys and have similar values. The dependence of minimum setting temperatures on the Al and Cu content in the solder was obtained. The authors studied the influence of the state of the base metal surface on the spreading area of the Zn-4%Al zinc solder during friction application. The experiments determined the zones of solder spreading over the surface of the AD31 aluminum alloy substrate, depending on the roughness of the base metal surface. The study identified that minimum setting temperatures of solders have similar values against the liquidus temperatures of these alloys, and the adding of copper to a solder reduces these temperatures, on average, by 20° С per each percent of added copper. The flowing of Zn–4%Al solder over the AD31 aluminum alloy surface reaches the largest values when treating the surface with rough-grain abrasive cloths, and the flowing effect decreases with the decrease in roughness.
The research of interaction of zinc solders with aluminum alloys during friction application
