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1. Digital Light Process 3D Printing of Magnetically Aligned Liquid Crystalline Elastomer Free–forms

   https://doi.org/10.1002/adma.202414209  

   Herman, Jeremy A; Telles, Rodrigo; Cook, Caitlyn C; Leguizamon, Samuel C; Lewis, Jennifer A; Kaehr, Bryan; White, Timothy J; Roach, Devin J (December 2024, Advanced Materials)

   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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2. Printing rare-earth-free (REF) magnetic inks: synthesis, formulation, and device applications

   https://doi.org/10.1039/D4NR04035J  

   Moni, Hur-E-Jannat; Rezaei, Bahareh; Karampelas, Ioannis H; Saeidi-Javash, Mortaza; Gómez-Pastora, Jenifer; Wu, Kai; Zeng, Minxiang (February 2025, Nanoscale)

   This review highlights recent advances in additive manufacturing of rare-earth-free (REF) magnetic materials, emphasizing innovations in material synthesis, ink formulation, printing techniques, and device applications. 

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3. Additive manufacturing of high‐density silicon carbide ceramics through post‐processing spark plasma sintering

   https://doi.org/10.1111/ijac.15167  

   Xiang, Yuhui; Doran, Spencer; Chang, Tzu‐Yi; Wang, Zexiao; Sangkagoon, Smitanan; Yeung, Yun; Xue, Fei; Cheng, Tian‐Le; Zhao, Dong; Lian, Jie; et al (May 2025, International Journal of Applied Ceramic Technology)

   Abstract This research advances the field of additive manufacturing (AM) of silicon carbide (SiC) ceramics by integrating spark plasma sintering (SPS) to enhance material density, mechanical strength, and thermal properties. Traditional AM techniques struggle to achieve the high‐density SiC required for demanding applications, such as aerospace engineering, where high thermal conductivity and mechanical strength are paramount. Our study addresses these challenges by incorporating SPS as a post‐processing step, achieving near‐theoretical maximum densities and significantly reducing porosity, thereby resulting in outstanding thermal conductivity in SiC ceramics. We developed a specialized SiC ink optimized for 3D printing, ensuring structural integrity after deposition through tailored rheological properties. The application of SPS facilitates rapid, uniform sintering, essential for attaining superior density, mechanical properties, and thermal performance. Our experimental results, confirmed through scanning electron microscopy analysis, demonstrate significant microstructural properties, mechanical strength, and thermal conductivity, showcasing the effectiveness of integrating SPS in AM processes. This innovative approach not only expands the capabilities of AM in producing complex, high‐density ceramic structures but also broadens the potential applications of SiC in demanding environments. 

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4. Review of the Use of Metals in Biomedical Applications: Biocompatibility, Additive Manufacturing Technologies, and Standards and Regulations

   https://doi.org/10.3390/met14091039  

   Ladani, Leila; Palmieri, Michael (September 2024, Metals)

   Advanced manufacturing techniques such as Additive Manufacturing (AM) have grown rapidly in major industries such as aerospace, automotive, and biomedical device manufacturing. Biomedical industry has benefitted immensely from AM because of its flexibility in design and its rapid production cycle. Powder bed processes are the major production technique for metal-based AM implants. This paper serves as a comprehensive review on the research efforts being made using AM to develop new patient centered medical devices. This review focuses on AM of the most common metals for biomedical applications, Magnesium alloys, Cobalt-Chromium alloys, pure Titanium, Titanium alloys. Several different aspects are discussed including biocompatibility and osseointegration, application of specific metals in different types of implants, their advantages and disadvantages, mechanical properties in comparison to bone, and their production technologies. Regulatory and quality assurance hurdles that are facing new innovations made using AM are discussed. 

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5. Go with the flow: Rheological requirements for direct ink write printability

   https://doi.org/10.1063/5.0155896  

   Wei, Peiran; Cipriani, Ciera; Hsieh, Chia-Min; Kamani, Krutarth; Rogers, Simon; Pentzer, Emily (September 2023, Journal of Applied Physics)

   The rapid development of additive manufacturing, also known as three-dimensional (3D) printing, is driving innovations in both industry and academia. Direct ink writing (DIW), an extrusion-based 3D printing technology, can build 3D structures through the deposition of custom-made inks and produce devices with complex architectures, excellent mechanical properties, and enhanced functionalities. A paste-like ink is the key to successful printing. However, as new ink compositions have emerged, the rheological requirements of inks have not been well connected to printability, or the ability of a printed object to maintain its shape and support the weight of subsequent layers. In this review, we provide an overview of the rheological properties of successful DIW inks and propose a classification system based on ink composition. Factors influencing the rheology of different types of ink are discussed, and we propose a framework for describing ink printability using measures of rheology and print resolution. Furthermore, evolving techniques, including computational studies, high-throughput rheological measurements, machine learning, and materiomics, are discussed to illustrate the future directions of feedstock development for DIW. The goals of this review are to assess our current understanding of the relationship between rheological properties and printability, to point out specific challenges and opportunities for development, to provide guidelines to those interested in multi-material DIW, and to pave the way for more efficient, intelligent approaches for DIW ink development. 

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