A common problem with brazed or soldered joints is galvanic corrosion, since the joint usually involves dissimilar metals in direct metal-to-metal electrical contact.
a. For each of the various solder or braze joints described below, determine which material will act as the corroding anode.
(1) Two pieces of low-carbon steel being brazed with a copper-base brazing alloy
(2) A copper wire being soldered to a steel sheet using lead-tin solder
(3) Pieces of tungsten carbide being brazed into recesses in a carbon-steel plate
b. How do the various lead-free solders compare to the conventional lead-tin solders with regard to their potential for galvanic corrosion?
c. If galvanic corrosion becomes a significant and chronic problem in a brazed assembly, what changes might you suggest that could possibly reduce or eliminate the problem?