It has been discovered that deep cryogenic treatment of copper resistance welding electrodes will dramatically increase their useful life. Conservatively, they now experience an increase in service life of at least 3 to 5 times over untreated electrodes. These particular electrodes are Mollory Class 3 and are used for welding caps on TO-3 headers (power transistors).
Service life of deep cryogenically treated electrodes is extended in three ways:
- Average life of the untreated electrodes is 5 days: after treatment they last 22 days.
- The untreated electrode is redressed by removing 0.008 to 0.010 inches of material; the treated electrode required only 0.003 to 0.005 inches of stock removed during each redress.
- Untreated electrodes can be dressed only 5 times before they must be scrapped; deep cryogenically treated electrodes can be redressed 10 times before they must be scrapped.