Build failure resulting from thermal stress in the part is one of the perils of laser powder bed fusion metal additive manufacturing (AM). Build time might be lost on a part that has already broken free of its supports, and therefore is already doomed to be scrapped. But by using a different additive process, a form of sheet lamination called ultrasonic additive manufacturing, Fabrisonic developed a build plate with embedded sensing able catch the moment when the forces in the part change abruptly, suggesting a failure has occurred. Ultrasonic AM is a solid-state process (no melting), making it possible to install a fiber optic line midway through the build before resuming the build to finish the solid plate and seal the sensing line inside. The result is a build plate able to catch the precise moment something goes wrong.

This is our fifth episode of The Cool Parts Show, but our first to deal with a part that is strictly for 3D printing.

The Cool Parts Show is a video series from Additive Manufacturing Media that explores the what, how and why of unusual 3D printed parts. Watch more here. Have a cool part to share? Email us.

Transcript

Peter Zelinski, Additive Manufacturing

An additive manufactured part helps make other additive manufactured parts. We get meta like that in this episode of The Cool Parts Show.

Peter Zelinski

I'm Pete.

Stephanie Hendrixson, Additive Manufacturing

I'm Stephanie.

Peter Zelinski

Welcome to The Cool Parts Show.

Stephanie Hendrixson

(musical interlude)

Peter Zelinski

Thanks again for watching The Cool Parts Show. I have a cool part made additively, where you have to be in additive manufacturing to appreciate the coolness of the part.

Stephanie Hendrixson

Pete, this looks like a build plate.

Peter Zelinski

It is a build plate, arguably the most boring component of the powder bed fusion metal additive process, but in powder bed fusion, what would you say is the biggest peril?

Stephanie Hendrixson

Probably build failure and not knowing that your build has failed until the very end.

Peter Zelinski

Yeah. So this build plate watches for build failure.

Stephanie Hendrixson

That's pretty cool. How does it do that?

Peter Zelinski

So this plate was made additively. A solid plate has a fiber optic sensor running all through it, capturing data in real time to monitor the build. This is additive manufacturing helping additive manufacturing.

Stephanie Hendrixson

So this plate was 3D printed with the fiber optic inside. How did they do that?

Peter Zelinski

Yeah. So it was not made through powder bed fusion. It's helping powder bed fusion. But it was made through a different process, a solid state additive process. This plate was made through ultrasonic additive manufacturing. No melting involved, no super high temperatures. This sensor cable was never in any danger. We talked about ultrasonic additive manufacturing in the very first episode of The Cool Parts Show. Here's a quick recap from Fabrisonic, which is the company that made this plate.

Mark Norfolk, Fabrisonic

So ultrasonic additive manufacturing is a type of 3D printing for metals. UAM is little bit different in that we're taking thin foils of metal on the order of five to ten thousandths of an inch and we're welding those together using ultrasound. The secret sauce there is we're not actually melting anything. This is all happening at room temperature. So what we do is we fold over the foil onto the material we want to bond and we roll over that with what we call an ultrasonic welder. As it rolls over, it's vibrating the sheet back and forth on the order of 20 thousand times a second. That vibration actually scrubs off any impurities, any oils, and most importantly, scrubs off the oxide layer. As soon as you have virgin metal touching virgin metal, Mother Nature takes over and you get a solid state bond.

Peter Zelinski

So ultrasonic additive manufacturing. This plate was built in layers, layers of metal foil bonded together. The build was paused halfway through. This fiber optic thread was snaked all through it all along the surface of the plate. And then the build resumed. Completely solid, one piece metal part with the sensor inside.

Stephanie Hendrixson

So you said this build plate can actually watch what's happening during the print. What is it watching for?

Peter Zelinski

Right. It is watching for stress, temperature and strain. This fiber optic sensor, it is threaded all along the area of the plate in different directions as it goes. It can measure strain along the direction of its length. So having it oriented in all different directions all along the plate lets it pick up different coordinate directions of the strain measurement. So strain can be measured as a vector. At pixel points in a grid all along the surface of this plate, that strain vector is being tracked while the build is happening. What it's really watching for are changes in those vectors, a sudden change in vector direction, a sudden change in the direction of strain at any one of those points. That's a sign something broke.

Stephanie Hendrixson

And so you can avoid those build failures by detecting the errors early.

Peter Zelinski

Yeah. And save yourself hours and hours of build time potentially just to make a scrap part. Once there's a build failure, you know it right away and you can start over.

Stephanie Hendrixson

This sounds really promising. Is this the final version of this build plate?

Peter Zelinski

Well, no. So here's more from Mark Norfolk, Fabrisonic. He has some ideas about where this could go next.

Mark Norfolk

Our initial try at a smart base plate, we kept all of our strain sensors in a single plane, which gives an amazing amount of data. We just recently were awarded a Phase 2 program where we're going to take this to the next level. And for us, the next level is actually to put in several different planes of data collection. By adding a second plane, one on top of the other, that's going to allow us to get data on moments or torque going through the plates, which will give us a whole other dimension of data that's just not available at this point.

Stephanie Hendrixson

All right. So to recap, this is a 3D printed build plate for powder bed fusion made with ultrasonic additive manufacturing. And that process allowed Fabrisonic to lay a fiber optic sensor all throughout, laid in different directions to track strain in different directions. It's also looking at stress and temperature and as a result of that, you can detect defects in the part before it's too late. You could stop the build right away, save lots of time, money, material.

Peter Zelinski

There you have it. Thank you for watching The Cool Parts Show. Tell us about your cool part. Maybe we do an episode on your part. We'd love that. CoolParts@AdditiveManufacturing.Media. Thank you for watching. Don't forget to subscribe.