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Polymer matrix composite materials with magnetic properties obtained by the addition of micron-size particles of neodymium iron boron (NdFeB) and strontium ferrite for fused filament fabrication (FFF) are becoming attractive because of their potential applications in the health and automotive industries. Additionally, the design flexibility and low cost of additive manufacturing processes encourage the scientific community to create the materials and understand the properties of the parts obtained with such methods. For example, the micron-size particles of NdFeB and two different types of strontium ferrites, OP-56 and OP-71, were dispersed in the Polyamide 12 matrix using twin screw extrusion. The monofilaments produced on twin screw extrusion were used to print test samples using an open-source FFF 3D printer. Thermal analysis shows a heat flow improvement in the composites compared to neat polyamide 12. Flexural and tensile strengths of the NdFeB/PA12 and OP-71/PA12 composites were reduced, whereas OP-56/PA12 composites showed an improvement of 6% compared to neat PA12. On the other hand, the tensile moduli of OP-71/PA12, OP-56/PA12, and NdFeB/PA12 composites increased by 5.5%, 48.9%, and 25.13%, respectively. 

Magnetic Field Assisted Additive Manufacturing (MFAAM) enables 3D printing of magnetic materials of various shapes which exhibit a complex anisotropy energy surface containing contributions generated from different origins such as sample, particle, and agglomerate shape anisotropy, flow and field induced anisotropy, and particle crystal anisotropy. These novel magnet shapes require the need to measure the x, y, and z components of the magnetic dipole moment simultaneously to fully understand the magnetic reversal mechanism and unravel the complex magnetic anisotropy energy surface of 3D printed magnetic composites. This work aims to develop a triaxial vibrating sample magnetometer (VSM) by adding a z-coil set to a pre-existing biaxial VSM employing a modified Mallison coil set. The optimum size and location of the sensing coils were determined by modeling the sensitivity matrix of the z-coil set. The designed coil set was implemented using 3D printed spools, a manual coil winder, and gauge 38 copper wire. A 3D printed strontium ferrite nylon composite sample was used to estimate the sensitivity of the z-coils (50 mV/emu). The results herein are applicable for any VSM using a modified Mallison biaxial coil configuration allowing for a quick implementation on pre-existing systems.