While spot welding of any components in automobile, switchgear and any other industry, one needs to know which would be good material for spot welding electrodes.
Since in the same field of resistance welding, I worked for 25 years. I would suggest Copper Chromium Zirconium copper alloy with hardness 75 HRB or above and conductivity 75 - 80 % IACS. You can refer RWMA classifications as per Class-2 copper alloy.
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