I try to dissolve solder on PCBs at room temperature and pressure with a solvent without damaging electronic components and Cu.
Hi Muammer,
From a friendly technological lab, I've learnt that the solvent you might be satisfied with would be formulated hydrocarbons. They were developed and, when perfectly formulated, can easily outperform any other solvent. They are able to remove flux residues, solid residues and salts under any type of components because of their very low surface tension (approx. 20mN/m). However, as with the aqueous process, the same detergent drawbacks exist, whereas, with the co-solvent process, the PCBs are very nicely rinsed and dried with the vapor phase fluorinated solvents. The rinsing solvent can be recycled by distillation and the formulated hydrocarbon is easily disposed of. The formulated hydrocarbons have a very extensive lifetime and because of this, the total costs are the lowest of all types of cleaning systems. The surface tension of both formulated hydrocarbons and fluorinated solvents is outstanding. This combination is one of the most user- and environmentally friendly processes.
Even less perfect but still pretty effective might be fluorinated solvents. When used pure, fluorinated solvents and formulations can not dissolve all contaminants. Even with the lowest surface tension ofall families, approx. 8-15 mN/m, their solvency power is weak. But when combined with formulated hydrocarbons, then the co-solvent process is excellent for handling the toughest solvent jobs.
Best wishes,
Ilya
While fluorinated solvents and hydrocarbons will remove flux residues there is no way they will dissolve metal solder. Solder is a metal - an alloy of lead and tin. Dissolving the metal with acids would work (but is dangerous) and would also destroy the components and the board. The only realistic way to remove the solder is by heating it to melt it either component by component or by floating the board on a bath of molten solder.
I would like to desolder all electronic components simultaneously from PCBs. Termal treatment is working; but, it is not possible to desolder PCBs less than 300 oC. Melting point of solder is 183 oC; but, I can't melt most of the solder less than 300oC. There is another problem with the high surface tension of solder. Solder does not flow away from the PCB surface. It gets melt but remain on the board. If you pull the electronic parts you can remove them. So there is an external force need to remove parts. Have can I remove the molten solder surface tension at around 300 oC? Another problem; when I use heat, most of the part may be damaged.
use Tin stripping agent readily available, within an hour solder removes detaching all the components.
Fluroboric acid (0.3M) with hydrogen peroxide (0.2M) selectively removes solder quite nicely. I forget the paper where I found the method, but I am sure it will come up with a quick search. The process is a bit pricey, but effective!
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