I've got to agree with Al to what he's saying... The only thing I'll add is this:
The only Aluminum alloy that may come close, yet still below a UTS of 100 ksi are the 7XXX Series Alloys – (heat treatable – with ultimate tensile strength of 32 to 88 ksi) These are the aluminum / zinc alloys (zinc additions ranging from 0.8 to 12.0%) and comprise some of the highest strength aluminum alloys. These alloys are often used in high performance applications such as aircraft, aerospace, and competitive sporting equipment. Like the 2xxx series of alloys, this series incorporates alloys which are considered unsuitable candidates for arc welding, and others, which are often arc welded successfully. The commonly welded alloys in this series, such as 7005, are predominantly welded with the 5xxx series filler alloys.
Hope this helps and if you want to know more about aluminum alloys, then please visit this link and explore it thoroughly:
http://www.alcotec.com/There are other good sites and the Aluminum association can teach you more, and yet this is a good starting point IMHO. ;) hope this helps. ;)
Respectfully,
Henry