Research on Stereolithography-Based Shape Memory Polymers/Fe₃O₄ Composite Ceramic Precursor Four-Dimensional Printing

Four-dimensional (4D) printing is a cutting-edge additive manufacturing technique that enables dynamic deformation of three-dimensional printed components under external stimuli. Polymer-derived ceramics (PDCs) feature excellent design flexibility, corrosion and wear resistance, but ceramic 4D printing still faces critical drawbacks including inferior deformability, low forming precision, poor slurry-photopolymerization compatibility, and single-response actuation limits. This study proposes an innovative strategy for high-resolution, programmable multi-responsive ceramic 4D printing to tackle these issues. We integrated stereolithography (SLA) with thermosetting shape memory polymers (SMPs) and Fe₃O₄/Al₂O₃ ceramic composites with magnetothermal conversion effects. The prepared composite slurries were systematically characterized, and an integrated process of stepwise curing and shape programming was constructed. Molecular dynamics simulations clarified the interfacial bonding between polymers and inorganic particles. The ceramic precursors achieve autonomous and precise shape recovery under magnetic or thermal stimulation, and the programmed geometries can be stably maintained as designed configurations. This work establishes a complete technical framework that synergistically integrates SLA-based high-precision forming, magnetothermal dual-responsive actuation, and programmable reconfigurability, enabling complex ceramic precursor structures with tunable shape memory effects. The strategy offers a viable route for smart ceramic fabrication and opens promising perspectives for applications in aerospace deployable structures and non-contact biomedical devices.