As stated in other articles in this blog copper is a very conductive material and has little resistance and will not heat up very much. Copper electrodes are not used. RWMA Class 13 or 14 refractory materials are used. They heat up and transfer heat into the copper. In many applications the copper is coated with a low melting material, which will melt and act as a brazing agent and bond the surfaces together. This joint can only be as strong as the interface material. Zinc and Tin are commonly used but are not very strong. This limits their effectiveness.
A better joint can be formed if a true resistance braze is performed by placing actual braze material in the joint. Heat this joint using the same resistance method until the braze material melts and fills the joint and is allowed to solidify under very modest pressure. Don’t squeeze the molten braze material out of the joint. This braze joint will be strong and durable.
Low Force Adjustable Holder
The following articles in this blog will further explain resistance brazing.
How do resistance brazing schedules vary from spot welds?
Resistance brazing is used regularly in the electrical industry to make attachments in their highly conductive copper and silver products.
References:
CMW Products Inc. Catalog
Tuffaloy Products Catalog
RWMA, Resistance Welding Manual, Section 6