What if any type of solution would degrade a silver braze alloy? 1

[EngineerDave]

To the best of your knowledge, could a alkaline cleaning solution degrade a silver braze alloy?

I could understand how some type of acid would cause degradation, but a alkaline solution?

Does anyone have any knowledge or experience of this?

Thanks in advance for any feedback

 

[tomwalz]

This comes up a lot in the saw repair industry. There are also questions about the carbide.

Typically I agree with this statement then go on to add that we tested it and it doesn’t make any practical difference.

Silver braze alloy is silver, copper, zinc, nickel, manganese, cadmium, tin and other metals in a wide variety of combinations. Plus it is often heated with an oxy acetylene torch using a flux typically potassium salts of boron and fluorine. This gives you the opportunity to form a great number of compounds, some of which may be affected by a caustic solution.
Plus the braze alloy is subjected to wear, heat, chemicals and tribological attack while in use. This creates an additional set of circumstances which could create substances susceptible to caustic attack.

We surface treat, pretin and braze WC, ceramics, etc. using silver braze alloy (silver solder, filler metals) We recommend that people use Easy Off oven cleaner for surface preparation on an experimental or other limited basis and a commercial, strong caustic solution to clean saws, and other brazed tools before brazing and before resharpening.

This changes the color of the braze alloy. Because it changes the color of the alloy it is assumed that it has a chemical affect as well.

Basically we tell people to take a piece of braze alloy, spray it with Easy Off and let it sit for an hour, day, weekend, week or whatever and see if they can tell any difference.

We work with a lot of really bright, conscientious people in shops and mills. Many of them do not have much education in chemistry. This leaves them susceptible to lots of rumors and distortions of the truth. I get to tell them they are right which makes them happy and then I give them a simple way to establish that they don’t really have a problem after all which also makes them happy. I find that if I can structure facts honestly so I give them good news they remember the facts much better.

Tom

See

http://www.carbideprocessors.com

for a lot more about this than you probably ever wanted to know