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Abstract Liquid crystalline elastomers (LCEs) are anisotropic soft materials capable of large dimensional changes when subjected to a stimulus. The magnitude and directionality of the stimuli‐induced thermomechanical response is associated with the alignment of the LCE. Recent reports detail the preparation of LCEs by additive manufacturing (AM) techniques, predominately using direct ink write printing. Another AM technique, digital light process (DLP) 3D printing, has generated significant interest as it affords LCE free‐forms with high fidelity and resolution. However, one challenge of printing LCEs using vat polymerization methods such as DLP is enforcing alignment. Here, we document the preparation of aligned, main‐chain LCEs via DLP 3D printing using a 100 mT magnetic field. Systematic examination isolates the contribution of magnetic field strength, alignment time, and build layer thickness on the degree of orientation in 3D printed LCEs. Informed by this fundamental understanding, DLP is used to print complex LCE free‐forms with through‐thickness variation in both spatial orientations. The hierarchical variation in spatial orientation within LCE free‐forms is used to produce objects that exhibit mechanical instabilities upon heating. DLP printing of aligned LCEs opens new opportunities to fabricate stimuli‐responsive materials in form factors optimized for functional use in soft robotics and energy absorption.
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Additive Manufacturing of Magnetic Materials for Energy, Environment, Healthcare, and Industry Applications
Abstract Recent advancements in additive manufacturing (AM) techniques have significantly expanded the potential applications of magnetic materials and devices. This review summarizes various AM methods, including ink‐based and ink‐free processes, and their use in fabricating complex magnetic structures with specific properties tailored for different fields. Key applications discussed include energy‐harvesting devices enhanced with magnetic nanoparticles, water decontamination through magnetically guided microswimmers, and magnetic soft composites in robotics and medical devices. In addition, the integration of AM in producing wearable and flexible magnetic sensors is highlighted, demonstrating its transformative impact on human‐machine interactions. Furthermore, rare‐earth‐free magnets and electric motor designs enabled by AM techniques are also discussed. Despite material compatibility and scalability challenges, AM provides opportunities for creating multifunctional, sustainable devices with reduced waste. Future research should focus on optimizing these techniques for complex applications and large‐scale production, particularly in eco‐friendly and industrial settings.
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- Award ID(s):
- 2418915
- PAR ID:
- 10576167
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 35
- Issue:
- 10
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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