Development of 3D printable Strontium Ferrite/ Polyamide 12 composites for magnetic devices (led by Dr. Tate):

The increasing demand in magnets for the transportation industry and lightweight consumer products requires fast and reliable manufacturing methods that use the materials efficiently and eliminate the number of tools needed for manufacturing [1]. Compared with Additive Manufacturing (AM), the traditional methods appear highly complex and expensive. Therefore, creating polymer composites with Magnetic Particles (MPs) for 3D printing is becoming an extensive area of research due to their superior properties [2,3]. Although some work has been done on 3D printed polymer composites with hard MPs such as SmCo, NdFeB, and NiZn, no commercially available filament to print permanent magnets is accessible for users. Preliminary investigation of nanocomposites based on ABS and PLA matrices focused on high particle sizes (48 µm) and low loading levels (40 wt%) [4], which results in a brittle behavior at higher filler concentrations and highly complicates the 3D printing process.

The main goal of this study is to manufacture SrFe₁₂O₁₉/PA12 nanocomposites for Fused Filament Fabrication (FFF) purposes by using a co-rotating twin-screw extruder. The use of highly stable SrFe₁₂O₁₉ allows magnetic particles with dimensions close to the single-domain particle size and avoids oxidation issues as encountered in composites using NdFeB particles. The objectives of this research are to 1) effectively compound the SrFe₁₂O₁₉ with polyamide 12 to produce filaments for 3D printing, 2) Characterize mechanical, thermal, and magnetic behavior of developed material and 3) Correlate materials performance with the structure of dispersed magnetic particles and compounding efficiency.

Dr. Tate leads this project.

---