We don't do much glueing of aluminum to steel where I work. In fact, steel is a pretty rare commodity. Lots of aluminum, fair amounts of titanium and magnesium. Lots of carbon fiber and fiberglass, too. Generally though, we don't glue pieces of metal together, they are usually fastened with rivets or bolts. Occasionally we do bond little aluminum brackets onto structures to hold up stuff like interior sidewall panels or some other non-structural application.
That said, a good epoxy like JB Weld or 3M epoxy (sorry, I forget the commercial name for it, but it's light blue when mixed), ought to do fine for something like this.