YES, AL is commonly used in buss bars, terminals, etc, in the electrical industry. BUT, it is almost always plated/coated with some other metal, like Tin. This coating keeps the AL from oxidizing, and therefore reduces the risks of using Aluminum.
AND, to me, when one says, "6061 is 42% of copper", when speaking of conductivity, read it as, 6061 is 42% as conductive as it Copper. Could also be read that it is composed of 42% Copper ...
That is a sporty table, indeed. But it is not clear what issue/concern it might be addressing.
It is beginning to appear that you really DO want to use AL busses, and perhaps these busbars might well NOT be coated or plated with a metal that will render them less unsafe ... it this correct ??Thanks, Vic