Exertions of Magnetic Polymer Composites Fabricated via 3D Printing

A breakthrough in the expanse of manufacturing techniques is rendered by the 3D printing technique which expanded the horizon to a broad range of applications. The advancement of manufacturing techniques made it efficient enough to print various magnetic polymer composite parts, which when authenticated into intricate structures can be utilized for distinct applications. This review provides a descriptive idea about the diverse magnetic polymer composites, their unique magnetic and mechanical properties, and the applications in which they can be involved, owing to these properties. Magnetic polymer composites are formed by the embedding of magnetic particulates into a polymeric matrix, and the magnetic characteristics thus arising contribute to various applications. Soft magnetic polymer composites generally find applications in dynamic systems, and polymeric composites composed of hard magnetic materials are predominantly utilized in shape morphing implementations. A change in the mechanical moduli in the presence and absence of a magnetic field is observed in the case of magnetic polymer composites, with the effect being termed as the magnetorheological effect (MR effect). A detailed overview on the MR effects of different magnetic polymers with different magnetic particulate concentrations between 10% and 20% responsive to various modes of deformations including pure shear, tension, and compression is included. Experiments conducted so far have reached a conclusion that a magnetic flux applied in the direction parallel to the particle alignment in the magnetic polymer composite can result in an improved value of the MR effect, and being more specific, a magnetic flux density of 67.5 Mt was able to develop up to a 74% MR effect. The extrusion of materials like NdFeB and Mn–Al alloys can be 3D printed for fabricating permanent magnets, for themselves being the end product or for the manufacture of magnetic gadgets. Fused deposition modeling of magnetic polymer composites is carried out for the production of transformer cores with toroidal geometry, with an improved efficiency at a lower cost. 3D printed microswimmers fabricated by the two photon direct laser writing technique (TDLW) of magnetic chitosan for light triggered drug delivery and the extrusion 3D printed representative models of human upper airways for the treatment of sleep apnea are other fascinating applications of 3D printed magnetic polymer composites. The convergence points of this review are various 3D printing techniques employed concerning magnetic polymer composites which include Fused Deposition Modeling (FDM), Direct Ink Writing (DIW), Selective Laser Sintering (SLS), and Digital Light Processing (DLP) and the characterization of the magnetic as well as mechanical properties which were affected by the embedding of magnetic particulates into the polymeric matrix such as uniaxial and biaxial tests, shear tests, etc., and the review discusses in detail the great number of applications of magnetic polymer composites in distinct fields such as in biomedical applications, electronics, soft robotics, etc.