EWI Logo on Product Example

Manufacturing Innovation for the Common Man – Linear Friction Welding (Part 3 of 8)

January 28, 2013

Here’s a test to see if you’re a Common Man… If I asked you (95% of the people reading this blog) to describe what welding is, I’m guessing you would describe one of two things: Arcs and/or Sparks.


When I started here at EWI as CFO, I pictured either a guy flipping down his welding mask, lighting a torch, and welding on a pipeline (arc welding) or an assembly line with robots and sparks (resistance welding). If you thought of either of these two, please keep reading… If you could think of more than those two, you should stop reading this blog and enjoy this video with the few minutes I just saved you.

So who knew there were dozens of other types of welding? Six years ago, not this common man.

One of these other methods where EWI has developed world leading expertise is Friction Welding. If you stop and think about the title, you can figure out the concept. Creating heat through friction (think rubbing your hands together). The heat between the two parts is what is needed to join the parts. One variant of friction welding getting a lot of media attention lately is Friction Stir Welding (learn about FSW here). I’m going to talk about two other friction welding variants here though: Inertia Friction Welding (next blog) and Linear Friction Welding.

So in practice how does this work? I’ll explain it with all the technical vigor you have come to expect.

First linear friction… Say you have a large metal part and want to attach a small metal part to it. Using linear friction welding, you (not really you, but a piece of equipment) would shake the small metal part. Then at just the right moment, you push the small part against the big part. The magic happens based upon the material types, the velocity of shaking, the area between the parts, the force of the “push”, and the time of the interaction of the materials. I’m sure there are more variables, but you get the idea (and listing any more would overly impress the technical experts at EWI I’m trying to annoy through my explaining their technology for the common man).

Linear Friction Welding… for the Common Man

What makes linear friction welding great? High bond strength, ability to join dissimilar materials, and reduced cycle times to name a few. Done correctly, you can create an incredibly strong bond because you are not melting the metal, but rather plasticizing it (full disclosure, I’m not the best guy to talk metallurgy, but I understand plasticizing is much better according to Jose Ramirez). You’ll hear people say it’s a “solid state bond”… And that’s a great thing.

So where do you find companies using this process? Linear friction welding machines have historically cost over $1M and up to $3M or more, so their applicability has generally been limited to high cost parts typically found in the aerospace market. Recently though, EWI acquired equipment from a company that has developed a unit that is considerably less expensive and has a much smaller footprint which should open up the technology (and benefits) to a much bigger commercial manufacturing population. I just saw a demonstration (I actually just watched our technician working on a project) of the equipment and it’s really pretty amazing.

Have some real questions about the applicability of linear friction welding world? Then please feel free to call or email James Cruz ([email protected] 614.688.5255), Jerry Gould ([email protected] 614.688.5121) or Josh Chance ([email protected] 614.688.5243) and hammer away.

Next up… EWI Modeling… If you have any other questions, please email me at [email protected] or post in the comments section below.  To read the series from the beginning, please start at “Fanfare…err… Manufacturing for the Common Man“.