How does a soldering iron weld aluminum parts?
In the maintenance of radio and home appliances, it is sometimes necessary to weld small aluminum parts, because the surface of aluminum parts is easily oxidized, and it is difficult for beginners to weld firmly. The author refers to the welding materials of aluminum parts and has achieved success through experiments. This article introduces these practical methods of soldering aluminum for reference.
First, apply flux to the welding part of the aluminum parts, then dip a hot soldering iron into tin and place it on the soldering place for preheating. When the temperature rises, the flux will change from thick to thin, then add some flux Solder, make the solder wrap the tip of the soldering iron, and then use the tip of the soldering iron to rub back and forth at the soldering place. The friction distance should not be too large, generally between 3 and 5mm so that the tip of the soldering iron can scratch the aluminum oxide film on the surface of the aluminum component.
Since the welding place is covered with molten tin and isolated from the air, it is impossible to produce a new oxide film, and the tin can stick to the aluminum part of the oxide film that has just been removed in time.
The equal row of molten tin changes from a spherical shape to a flat shape, indicating that the aluminum part has been firmly bonded to the tin. At this time, stop rubbing and wipe off the remaining solder while it is hot, and then weld it with the wire head or other components that have been dipped in tin in advance. It is very convenient.
Second, drop a few drops of dilute hydrochloric acid on the welding part of the aluminum component to remove the surface oxide film, wait for a while, then add a few drops of thicker copper sulfate solution, and when the welding part is completely covered with copper, wash off the excess with water. Copper sulfate solution and hydrochloric acid solution, and then use a 45-75W soldering iron to solder, and the effect is good.
Third, take a piece of aluminum and put it into a crucible to heat and melt it, then add 2 to 5 times of tin and melt it for later use, and it is very convenient to weld according to the conventional method.
Fourth, apply a layer of mercury nitrate solution on the cleaned aluminum surface, use a 100w soldering iron tip to eat more tin, and rub the soldering iron tip on the welding surface while applying mercury nitrate solution. This can be firmly welded.
Note: Mercury is poisonous, welding should be done in a ventilated place, and highly toxic mercury chloride should not be used.
Fifth, the aluminum parts are welded by the local method, and the white powder for sawing the glass fiber board is prepared in advance, placed on the surface of the welding place, and rubbed vigorously on the welding surface with a 75w soldering iron until a layer of tin is attached to the aluminum surface, and then wipe it with a cloth. The mixture of white powder and rosin is removed, and then the general method can be used for welding. After practice, this method is simple and the welding effect is satisfactory.
It is also possible to mix rosin and iron filings, then use sandpaper to polish the surface of the aluminum part, put the rosin and iron powder on the smooth surface of the weld, rub repeatedly with a soldering iron to coat the aluminum surface with a layer of tin, and then follow the general method. Weld smoothly.
Sixth, first polish the surface of the welding part of the aluminum parts brightly, then drop a few drops of sewing machine oil, the amount of oil should be sufficient, then use a sharp knife to scrape the welding part back and forth several times, then use a soldering iron dipped in solder and rosin to go back and forth on the welding part With friction, the tin will quickly and firmly adhere to the aluminum parts. This method is also relatively simple and practical.
