nope...impossible to weld aluminum to steel. they're 2 very different substances...steel contains carbon and aluminum does not. in fact, if any carbon mixes w/ aluminum it weakens it. also, the melting point of both materials is too far apart to do any good welding. the only way to attach the two would be by brazing or silver soldering, but i'm not sure if that would even hold very well. or you could try bolting the 2 materials.
There are kits you can buy for joining dissimilar metals but I think it is rare that you might need something like this.
Brian Maas
Explosion Welding is a process used to join aluminum to carbon steel. The welding handbook volume 2 Chapter 24 8th edition has an informative section on this process. In addition to aluminum. Titanium, gold, silver copper and other metals are listed.
Here is a company that actually performes these operations.
http://www.dynamicmaterials.com/clad/clad.htm
Good Day
Gerald Austin
You can only weld steel to aluminum using a solid state process, such as explosion welding, friction welding, etc.
I've never had to join the two, so it never crossed my mind whether it could be done or not.
Good post,
John Wright
Something to think about.
At what temp does Steel melt?
At what temp does Alluminum melt?
Most folks think of welding as a Homoginise blend of materials.