[don alchemy]

i am building a aluminum battery box from diamond plate alum....and i want to weld it to the frame parts of my coupe.......is it possible to weld alum diamond plate to mild steel?......thanks in advance....

[lowROLLERchevy]

no its not, best bet is to bolt it in

only way to "weld" aluminium and steel is thru an explosion welding process i saw on discovery channel ....

[oldred]

Aluminum can not be welded to steel, don't even try it

[Lonestar]

Originally Posted by oldred

Aluminum can not be welded to steel, don't even try it

It can be done...

Explosive welding: http://www.metalwebnews.com/howto/ex...e-welding.html

Friction Stir Welding:
http://faculty.icc.edu/eockerhausen/...20Overview.pdf

Cold Metal Transfer:
http://www.axson.se/pdf/fro_bro_CMT_eng.pdf

[oldred]

Very interesting, but of course I meant in the normal sense that we think of for welding.

[grouch]

What about brazing? Is there a 3rd metal below the melting points of aluminum and steel that can be used to join those two?

[h0trod389]

weld a nut in the frame...
drill a hole in the battery box....
AND BOLT THE DARN THING!!

[powerrodsmike]

Thats some interesting stuff ,lonestar.

The explosive welding process you found is not really suited to home use. I think the mistakes a novice could make while learning this process could wind up being costly.

Friction stir welding is a little more acessable for the do it yerselfer, as it is mechanical, and a much safer method than the first ,but aluminum can only be joined to aluminum or copper with that process. Bummer.

The cold fusion process looks to be the most promising.
The smallest welder they make is a 320 amp unit with 2 computer controlled wire feeder units and computer controlled arc unit.
It didn't say if you needed the robotic arm to weld with it but it did say it was adaptable to all automated processes.

I'm just guessing here, but I'll bet the welding equipment alone is in the neighborhood of 20 or 30 thousand dollars.
Maybe Harbor frieght will come out with one soon and bring the cost down.
If you have to buy the robot and train it that might add 100 thousand or more dollars. Maybe, I havn't bought a robot arm for my welder lately.

I wonder if the OP's dryer outlet is 3 phase? He may need to hop up his electrical service a little.

I'm not really picking on you ,lonestar. I'm just having a little fun. Don't think I havn't heard of some bizzare welding processes myself.
I have a friend who works for NASA/ames research as a fabricator and teaches welding courses. He said he knows of a guy who created a process that fuses steel and glass. Think of what that will do for the auto industry.

Grouch- I could have sworn that I saw some super duper alloy rod like the stuff CMuggy sells that would solder dissimilar metals. I would not use it for anything structural though.

MY opinion? I'd be inclined to bolt that battery box on the frame.

Later, mikey

[grouch]

Originally Posted by powerrodsmike

[...]
Grouch- I could have sworn that I saw some super duper alloy rod like the stuff CMuggy sells that would solder dissimilar metals. I would not use it for anything structural though.

Powerrodsmike, thanks (and not just for the above quoted info). I always thought of soldering as involving a soft metal and weak joint, while brazed joints have strength suitable for structural work. That's a layman's viewpoint, though, and could be totally wrong. I'm going to do some searching for joining aluminum and steel, even though I sure can't argue with the several recommendations to just bolt it. It's just interesting to me.

[powerrodsmike]

My welding data book says that the AWS defines brazing as the joining of 2 metals at a heat higher than 800F, the use of a filler metal with a melting point lower than the base metal, with the qualification that the filler metal must wet the base metal surfaces and be drawn by capillary action into the joint.

I could find no reference to "soldering" in that book.

I also found several "soldering" definitions in other places that were worded exactly the same.


Here is one online definition that I found that differentiates between the definitions of soldering and brazing:

Joining metals by fusion of alloys that have relatively low melting points - most commonly, lead-base or tin-base alloys, which are the soft solders. Hard solders are alloys that have silver, copper or nickel bases. Use of these alloys with melting points higher than 800(F, 427(C is properly called "Brazing".

So the difference lies in the filler material, not the technique .

I learned something too

I know there have been a few of my projects that I would have used that above referenced explosive welding method on, and would have been glad if it failed.


later, mikey

[grouch]

That's similar to the definitions I ran into, also.

From http://www.jwharris.com/jwref/faq/#def
"What is the difference between soldering, brazing and welding?
"Soldering - The AWS defines soldering as a group of joining processes that produce coalescence of materials by heating them to the soldering temperature and by using a filler metal (solder) having a liquidus not exceeding 840ºF (450ºC), and below the solidus of the base metals.

"Brazing - Brazing joins materials by heating them in the presence of a filler metal having a liquidus above 840ºF (450ºC) but below the solidus of the base metal.

"Welding - In welding, fusion takes place with melting of both the base metal and usually a filler metal."


Haven't found anything specific to brazing aluminum to steel. There is a melting point chart here:
http://www.brazing.com/techguide/FAQ.asp

[powerrodsmike]

I think this is true, you can braze aluminum to copper, and you can electroplate copper on to steel .....I wonder if you could then join the aluminum to the copper clad steel?

Or is it bronze

I still like bolts for holding a battery box on a hotrod frame.

Grouch-I like that harris definition you found. it defines the filler metal characteristics better for the purposes of definition.

Mikey.

EDIT:
It was in the stuff grouch linked to. It can be done but it is difficult and not reccomended.

Bolts.