I'm going to reuse brazed crash tungsten carbide grits (it is WC with irregular shape). I am looking for a solvent to completely dissolute the braze alloy (Cu40Zn10Ni), without any damage on WC grits. What is the best solvent to remove braze alloy? Are there another way?
Thanks
At first, I'd try acids, because it is the common way to dissolve metals. Zn is dissolved by dilute HCl, but Cu is more difficult to dissolve in acids. You may try on the brazing alloy alone. But it seems that WC is attacked by strong acids (nitric and fluorhydric). I have no other info on WC resistance to acids. I found a patent (United States Patent 3958984, available on Google Patents) describing "A method of removing high temperature brazing alloys from a stainless steel base..." using alkali cyanides but I do not recommend to use cyanides (poisons and may generate the lethal gas HCN) unless you are well equipped chemical lab.
Can you selectively melt the braze and suck it out using vacuum - like how the solder in a circuit board is removed by melting and vacuum sucking!?!
The problem with the brazing is that it is supposed to interact strongly with the materials in contact, and to stick to the surfaces. I suppose that only a chemical treatment could remove the brazing.
- Badges
- Science topic