Dissimilar Metals/Sintering

By KPI Date 11-13-2001 17:33

We are having difficulty welding copper to bronze using wire fed mig with argon shielding. The welds seem to hold, but the copper becomes brittle and breaks. Could we be getting some type of hydrogen embrittlement? Would annealing or some type passivation help? Should we try brazing instead?

Thanks

By - Date 11-13-2001 18:08

If the copper is commercially pure copper as used in electrical conductors, then you should have no difficulty welding this. (Besides the heat input problems.)

There are however a number of different Cu alloys around. Do you know what you have?

Also, was the copper in service before the welding? If so, what service? It may be possible that the copper was attacked by some environmental degradation mechanism, and the welding is merely highlighting it.

The process of choice for welding Cu is in fact GMAW, (MIG) so this would not be the problem.

Hope this helps

Regards
Niekie jooste