Please accept my apologies, I assumed that you had really basic access to Internet reference and the required brain power with which you could work out from the prolific use of Aluminium alloys in Aircraft that for a similar weight a suitable Aluminium Alloy can provide greater stiffness for a given weight than any Iron based Alloy.
From there it should be a basic mathematical job to compare size and strength, and hey, if you're lazy then someone else might do the work for you:D