Perhaps you’ve heard of explosion welding? Yes, there is such a thing! If you’ve never heard of it, just a quick, very basic explanation: explosion welding takes two separate pieces of metal and, via the force of the explosion, welds the pieces together. It just sounds cool and epic, right?
Explosion welding is very effective for extra large pieces of metal that are harder to wrangle, as well as bonding completely different metals together that one could not conventionally weld. But, as you can imagine, explosion welding can’t happen in just any old place. And not everything we weld is humongous and worth the energy of explosion welding.
One of the alternatives to explosion welding is called Magnetic Pulse Welding (MPW). It’s not brand new…apparently it’s been around since the 1960’s & 70’s. However, it used to be lesser known and was only used for exclusive applications related to nuclear stuff & the automotive industry – today it is being used for a broader array of applications.
As you may have guessed from the name, Magnetic Pulse Welding uses a powerful electromagnet to weld two pieces of metal together. Just metal, the magnet and an electric current! Oh, and someone to set it up and press the button 😉 The two metals collide at such a high rate of speed that electrons are actually exchanged, fusing the metals at the molecular level. Again, a similar process happens with explosion welding, but with MPW – no explosion. Everything is neat and tidy and can be done on a much smaller scale.
Like explosion welding, MPW can weld disparate metals, for example steel bonding to aluminum or nickel to titanium. That, my friends, is pretty cool! I’m sure the alchemists of the Middle Ages would have thought MPW was the bomb.com (pun there, see that?).
For those who are used to welding the old-fashioned way, there is really no end to the upside of MPW:
- No welding arc to protect your eyes from, therefore, no welding hood
- No gas bottles to hook up
- No hot sparks falling down your shirt, boots or into your ears
- No ground to clamp and no leads, rod or stinger to keep track of and not trip over
- No striker, either
- No welding fumes to worry about
- No grinding or chipping to get rid of unsightly slag
- No leather gloves needed because apparently, this process happens at room temperature!
- No welding truck…’cause…no welding machine needed
- There are probably more, but I can’t think of them now because I am making a cup of cappuccino. And wondering if there will ever be a Magnetic Pulse Espresso machine that can whip out a frothy mocha in the time it takes to blink?? We can only hope.
The downside to Magnetic Pulse Welding?
- Did I say cost already??
- Portability…I imagine the magnet & it’s set up will not be easy to just pack up and move to a customer’s job site (but I would be interested to see if more portable options are in the works!)
- And size will most likely be a factor. If you need a large piece welded and your magnet and accompanying machinery is not big enough, well then, don’t get rid of your welder and hood just yet.
As with anything that is amazing and a techno-wonder, cost will be a factor. You knew that was coming, didn’t you? However, the interwebs assure us that once you have laid out the significant amount of cash needed to acquire your fancy magnet, the cost of MPW is actually cheaper than more conventional methods of welding. I believe it – have you seen the price of welding supplies lately? Maybe the magnet is one of those things that will pay for itself in 5 years? Don’t run out and take out a loan based on that, of course. But this Magnetic Pulse Welding might be something to look into.
Cool websites, articles and videos to check out if you would like more information on MPW:
- UPDATE 7.6.18 – A new, very detailed article on this very subject, specifically copper/aluminum and copper/steel being magnetically welded: article in Machine Design “The JOIN’EM Project: How to Join Dissimilar Metals with Electromagnetic Welding”
- https://www.bmax.com/technology/magnetic-pulse-welding/ – Company in France who manufactures MPW technology – you should check out their info on Magnetic Pulse Forming as well!
- https://youtu.be/DAddzH6lutk – BMAX demonstration on flat metal
- https://youtu.be/UGHtrLhqQ9w – BMAX demonstration on tubes
- https://www.economist.com/news/science-and-technology/21697799-cleaner-sharper-way-weld-and-shape-metals-getting-pulse-racing – Catchy title, eh?
- https://awo.aws.org/2016/05/taking-the-explosion-out-of-explosion-welding/ – Explosion welding, how it happens, and alternatives to it, including MPW
- https://www.thefabricator.com/article/tubepipefabrication/magnetic-pulse-welding-for-tubular-applications-discovering-new-technology-for-welding-conductive-materials – Older article from 2001, but great info!
- https://www.assemblymag.com/articles/84188-the-cold-welding-process-is-being-used-for-more-and-more-high-volume-applications – Another older article, but great details on MPW and its origins