Authors Alan Shen, Xiaoguang Peng, Callum P. Bailey, Sameh Dardona, and W.K Anson explore new techniques in ‘3Dprinting of polymer-bonded magnets from highly concentrated, plate-like particle suspension.’ While magnets have been created previously via UV-assisted direct writing (UADW), there were challenges in the project due to limitations posed by particle types, loading, and viscosity levels. The authors modeled some of their work here after the Farris effect, in mixing particles of two different sizes and reducing viscosity.
3D printing magnets with polymer is increasing in popularity with researchers due to the minimal amount of tooling required, and lack of material waste. While use of the UADW method has been most successful thus far, the researchers for this study dispersed ferromagnetic particles (NdFeB) in a polymer binder, creating a paste to be extruded and then cured under UV light.
Performance is enhanced by increasing the magnetic powder to non-magnetic binder ratio, but there is the risk of particle jams and clogs.
“Further, the ink viscosity may also become too high to be printed, as limited by the printing pressure and flow instabilities,” state the researchers. “Physically, the increase of viscosity is caused by an increase in both the hydrodynamics interactions and particle-particle interactions as the particle loading increases. At exceedingly high particle loadings, particle-particle interactions become increasingly important.”
While printing with concentrated non-spherical particles can be challenging, the researchers aimed to understand more about particle size and structure in relation to suspension rheology. NdFeB powders were average in size, with a spherical diameter ranging from 5 to 200 μm. Particles with high aspect ratios align progressively along the shear plane as the shear rate increases, leading to reduction in viscosity and shear thinning.
“The resulting magnets have an intrinsic coercivity (Hci) of 9.30 kOe, a remanence (Br) of 5.88 kG, and an energy product ((BH)max) of 7.26 MGOe,” stated the researchers, adding that the corresponding values are the highest in the literature of 3D printed magnets.
The samples created for the research not only ‘rival’ magnets created through more conventional methods like casting, but they are versatile for creating parts with different structures, and both shape and topology that can be further optimized.
As 3D printing lends itself to so many different industries, materials, and mediums today, users are finding ways to refine a wide range of items for their own project requirements. This includes a variety of different magnetized materials, from composites to metamaterials and even ink for fabrication of shape-shifting objects. What do you think of this news? Let us know your thoughts! Join the discussion of this and other 3D printing topics at 3DPrintBoard.com. [Source / Images: ‘3Dprinting of polymer-bonded magnets from highly concentrated, plate-like particle suspension’]
“Scientifically, the rheological data presented in this study provides the basis for understanding and modeling highly concentrated suspensions of non-spherical particles, which remains largely unexplored. Technologically, the magnetic performance of 3D printed magnets may be further improved through material formulations and process control,” concluded the researchers.
“Of particular interest is to explore the use of anisotropic magnetic particles and how to control their alignment through in-situ processing  or post-processing, which may lead to even stronger magnets as suggested by other authors,” concluded the researchers.
You May Also Like
New Research Summary of 3D Printing Materials and Methods for Batteries and Supercapacitors
Because the technology can achieve complex shapes and structures and multifunctional material systems, a trio of researchers in Ireland – Umair Gulzar, Colm Glynn, and Colm O’Dwyer – were interested...
Hybrid 3D Printing: Comparing High-Frequency Filters with Conventional Methods
In the recently published ‘High-Frequency Filters Manufactured Using Hybrid 3D Printing Method,’ authors Ubaldo Robles, Edgar Bustamante, Prya Darshni, and Raymond C. Rumpf outline the development of two varying devices....
Generative Design, Digital Twin, WAAM 3D Printing Used to Optimize Industrial Robot Arm
3D printing specialist MX3D has been working on a metal AM technology to create large items, such as bicycles and bridges, using robots. Now, the Dutch startup has partnered up...
Korea: 3D Printing Complex Transparent Displays
In the recently published ‘High-Resolution 3D Printing of Freeform, Transparent Displays in Ambient Air,’ researchers from Korea are studying complex geometries in the form of optoelectronic architectures. If you are...
View our broad assortment of in house and third party products.