TU Wien Researchers 3D Print Strong Permanent Magnets, Offering Greater Potential for Sensors

Sometimes it seems hard to imagine what firsts could possibly be left in 3D printing, but they keep on coming. And now, researchers have created the first permanent magnets using this versatile technology. Meant to open up the world of magnet manufacturing further, while they can be made easily and with strength already, what is more challenging is to make a magnet with a field that bears a customized shape.

As the research team from Vienna’s Technische Universität Wien (TU Wien) turned to 3D printing, they discovered how its benefits could apply to their goals in creating strong permanent magnets. They outlined their findings in the paper, ‘3D print of polymer bonded rare-earth magnets, and 3D magnetic field scanning with an end-user 3D printer‘, published recently in Applied Physics Letters.

Offering one more step in bringing the manufacturing revolution to fruition, the researchers can make these magnets in more complex forms. With the customized fields, they can be used in sensing systems.

“The strength of a magnetic field is not the only factor. We often require special magnetic fields, with field lines arranged in a very specific way – such as a magnetic field that is relatively constant in one direction, but which varies in strength in another direction,” Dieter Süss, Head of the Christian-Doppler Advanced Magnetic Sensing and Materials laboratory at TU Wien, explains.

With the ability to construct the magnets in more complex geometries with the pre-determined field shapes, many new opportunities become possible.

“A magnet can be designed on a computer, adjusting its shape until all requirements for its magnetic field are met,” says doctoral student Christian Huber.

Molds are not required in this process as the specially designed magnet printer extrudes magnetic micro granulate, bonded with a polymer material. The 3D printed material is only ten percent plastic, with the rest being materials that are not yet magnetized. That happens at the end as the 3D printed items are converted into the permanent magnets, upon being exposed to the strong external magnetic field.

“This method allows us to process various magnetic materials, such as the exceptionally strong neodymium iron boron magnets. Magnet designs created using a computer can now be quickly and precisely implemented – at a size ranging from just a few centimeters through to decimeters, with an accuracy of well under a single millimeter,” says Süss.

As researchers use all of the benefits of 3D printing for creating a new world of magnets from customization and speed in production to the use of new and inventive materials, we will very possibly see more of this type of manufacturing in the future with more than one material being used within one magnet. They will offer a greater opportunity for transitioning between different levels of magnetism.

“Now we will test the limits of how far we can go – but for now it is certain that 3D printing brings something to magnet design which we could previously only dream of,” Süss concludes.

The paper’s authors in full as cited include C. Huber, C. Abert, F. Bruckner, M. Groenefeld, O. Muthsam, S. Schuschnigg, K. Sirak, R. Thanhoffer, I. Teliban, C. Vogler, R. Windl and D. Suess. Discuss in the 3D Printed Magnets forum at 3DPB.com.

[Source/Images: TU Wien]