How to solder aluminum reliably without flux
Using the proposed method, you can solder not only an aluminum wire to a copper wire, but also solder a hole in an aluminum pan with copper material. Let's start with the usual tinning of copper wire using rosin and tin solder using a soldering iron.
How to solder aluminum without special flux
To tin an aluminum wire, you will need a more powerful soldering iron, since aluminum is very thermally conductive and, as it were, draws heat from the soldering iron and complicates the tinning process. You will also need a paraffin or wax candle.
Paraffin or wax will replace rosin, that is, act as a flux. Next, we rub in tin solder, periodically dipping the aluminum wire into molten paraffin or wax to protect the surface of the aluminum wire from contact with the atmosphere and prevent the formation of an oxide film.
Let's start soldering the aluminum wire to the copper wire using conventional flux - rosin and tin solder. Since both wires are tinned, soldering proceeds as standard and with excellent quality.
We wait for the solder to harden and check the strength of the resulting solder.To do this, we pull the ends of the wires in different directions with all our might and clearly see that the strength of the connection exceeds the strength of the hands of an adult. Also, soldering can easily withstand bending deformation without loss of strength.
According to the laws of electrical engineering, it is strictly forbidden to connect copper and aluminum, since oxidation occurs at the soldering site, resistance increases and sparking occurs, which can lead to a fire.
But our connection is safe, since we soldered not aluminum to copper, but tin to tin, i.e., a kind of gasket in the form of tin solder was formed between the copper and aluminum wire.
