brass welding 3

[jorell]

Hi there, new member here with a question. I am having trouble welding brass. I've tried TIG welding it but could not get enough heat, and the brass exploded and contaminated. I tried oxy welding it but the brass wire would not flow with the parent material (bronze railing). Should I use a special flux? Preheat before TIG welding? Any help greatly appreciated!

Thanks, Jorell
onespeedlove@hotmail.com

 

[amorrison]

fwiw

I tried to SOLDER a copper tab to the outside of a brass valve once - it didn't work. The brass surface seems to have some inpurities in it. The answer was to file off the surface "material" and solder to the "good" brass underneath.
If your brass item is cast maybe the "polluted" surface is the problem.

 

[ornerynorsk]

TIG welding should be aces for brass. Metal prep and cleanliness is crucial.

 

[stanweld]

To better assist you, can you provide the alloy grade of both the brass and bronze materials that you are welding?

 

[deanc]

Try bronze or silver brazing. Contact your welding supplier.

 

[rd400guy]

First off, due to the high thermal conductivity, maintaining a high heat input is critical, so you should definitely preheat. What is the thickness of material? As you approach thicker sections (~1&quot you may need to preheat between 600F and 1000F depending on joint design.

The biggest problem with brasses is zinc fuming. Are you welding a high brass (20% to 45% Zn) or a low brass (20% Zn or less)? In any case, if you're using GTAW, try to keep the arc on the filler metal and weld puddle to minimize zinc fuming. Preheat 200F to 600F.

If it's a low brass, try a silicon bronze (ERCuSi-A) or phosphor bronze (ERCuSn-A) filler metal with GTAW(dcen), that is if you're using filler metal. You can also GMAW(dcep) with argon shield gas and preheat. Use a brass welding rod (ERCuZn-B, or -C) for OAW.

For high brass, the zinc fuming will be more pronounced. Again use a silicon bronze filler with GTAW. The weld metal will not be as strong as base metal. If you need higher strength, go to an aluminum bronze (ERCuAl-A2) filler metal, but this will be less effective in controlling zinc fuming. GMAW can also be used, with the same filler metals mentioned above. You can also gas weld high brass using a brass filler rod (RCuZn-A, -B, or -C). Use a slightly oxidizing flame (to control zinc fuming) and boric acid-borax type flux (AWS Type 5).

Let us know how it works out.