121228-0803 EST
edward:
Since you may not have easy access to the reference I provided here is some of the information.
The equation used is I = K*d(3/2) where I is fusing current in amperes, K a constant based on the material, and d the wire diameters in inches.
For # 6 wire (0.1620" dia) the values provided are:
668 A, K=10244, copper
495 A, K= 7585, aluminum
341 A, K= 5230, german silver
208 A, K= 3148, iron
107 A, K= 1642, tin
Not stated, but we can assume that these are uninsulated wires in still air, vertically mounted and of sufficient length that the end terminations don't greaterly alter the heat transfer at the center of the wire. Probably very little tensile load.
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