| Author(s) |
Pratik U. Karkhanis, Shourav Ghosh, Mir Imran Bin Samad, Roshan Poudel, Stirling Moss, Joben Rios, Wyatt Lange , Jitendra S. Tate |
| Abstract Scope |
Polymer-bonded magnets are widely used for sensing, actuation, and electromagnetic interference (EMI) shielding due to their design flexibility; however, their use is limited by the inherent flammability of conventional polyamide–ferrite systems. With the growing adoption of fused filament fabrication (FFF), there is a critical need for fire-safe, magnetically functional materials compatible with additive manufacturing. This study presents a halogen-free, flame-retardant, bonded-magnetic composite based on a polyamide 6 (PA6) matrix incorporating strontium ferrite, melamine polyphosphate (MPP), and glass fibers. The composite is fabricated via single- and twin-screw extrusion to achieve uniform dispersion, robust interfacial interactions, and stable processing for FFF. A synergistic phosphorus–nitrogen flame-retardant mechanism enhances char formation and thermal stability. Flame retardancy is evaluated using the Limiting Oxygen Index (LOI), along with TGA, DSC, SEM, and VSM characterization. The composite retains anisotropic magnetic behavior after printing, enabling functional performance in fire-critical additive manufacturing applications. |