Ceramics are an important class of materials with widespread applications because of their high thermal, mechanical, and chemical stability. Computational predictions based on first principles methods can be a valuable tool in accelerating materials discovery to develop improved ceramics. It is essential to experimentally confirm the material properties of such predictions. However, materials screening rates are limited by the long processing times and the poor compositional control from volatile element loss in conventional ceramic sintering techniques. To overcome these limitations, we developed an ultrafast high-temperature sintering (UHS) process for the fabrication of ceramic materials by radiative heating under an inert atmosphere. We provide several examples of the UHS process to demonstrate its potential utility and applications, including advancements in solid-state electrolytes, multicomponent structures, and high-throughput materials screening.

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Here we report the first example of a class of additively manufactured carbon fiber reinforced composite (AMCFRC) materials which have been achieved through the use of a latent thermal cured aromatic thermoset resin system, through an adaptation of direct ink writing (DIW) 3D-printing technology. We have developed a means of printing high performance thermoset carbon fiber composites, which allow the fiber component of a resin and carbon fiber fluid to be aligned in three dimensions via controlled micro-extrusion and subsequently cured into complex geometries. Characterization of our composite systems clearly show that we achieved a high order of fiber alignment within the composite microstructure, which in turn allows these materials to outperform equivalently filled randomly oriented carbon fiber and polymer composites. Furthermore, our AM carbon fiber composite systems exhibit highly orthotropic mechanical and electrical responses as a direct result of the alignment of carbon fiber bundles in the microscale which we predict will ultimately lead to the design of truly tailorable carbon fiber/polymer hybrid materials having locally programmable complex electrical, thermal and mechanical response.

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High-resolution 3D printing of intricate graphene aerogel micro-architectures with enhanced mechanical properties at decreasing densities.

Advances in additive manufacturing techniques have enabled the creation of stimuli-responsive materials with designed three-dimensional (3D) architectures. Unlike biological systems in which functions such as sensing, actuation, and control are closely integrated, few architected materials have comparable system complexity. We report a design and manufacturing route to create a class of robotic metamaterials capable of motion with multiple degrees of freedom, amplification of strain in a prescribed direction in response to an electric field (and vice versa), and thus, programmed motions with self-sensing and feedback control. These robotic metamaterials consist of networks of piezoelectric, conductive, and structural elements interwoven into a designed 3D lattice. The resulting architected materials function as proprioceptive microrobots that actively sense and move.

The trade-off between processability and functional responses presents significant challenges for incorporating piezoelectric materials as potential 3D printable feedstock. Structural compliance and electromechanical coupling sensitivity have been tightly coupled: high piezoelectric responsiveness comes at the cost of low compliance. Here, the formulation and design strategy are presented for a class of a 3D printable, wearable piezoelectric nanocomposite that approaches the upper bound of piezoelectric charge constants while maintaining high compliance. An effective electromechanical interphase model is introduced to elucidate the effects of interfacial functionalization between the highly concentrated perovskite nanoparticulate inclusions (exceeding 74 wt%) and light-sensitive monomer matrix, shedding light on the significant enhancement of piezoelectric coefficients. It is shown that, through theoretical calculation and experimental validations, maximizing the functionalization level approaches the theoretical upper bound of the piezoelectric constant d 33 at any given loading concentration. Based on these findings, their applicability is demonstrated by designing and 3D printing piezoelectric materials that simultaneously achieve high electromechanical sensitivity and structural functionality, as highly sensitive wearables that detect low pressure air (<50 Pa) coming from different directions, as well as wireless, self-sensing sporting gloves for simultaneous impact absorption and punching force mapping.barium titanate (BTO) [5] are the most frequently used piezoelectric ceramic materials for transducer applications. Direct 3D printing of piezoelectric-polymer composites offers a promising solution to fabricating complex piezoelectrics beyond conventional ceramic processing methods which require extensive, time-consuming sintering, may have residual porosity, and have brittle responses. However, due to the functionality-processability tradeoff, the resulting piezoelectric response of the printed nanocomposite is over two ordersof-magnitude lower than pure ceramic. [6] Increasing particle concentration leads to agglomeration, [7] high viscosity, [8] and significant light absorption, [9] making it difficult to manufacture fully complex microarchitectures or free form-factors. Additionally, the incompatibilities between high stiffness nanoparticle and low stiffness polymer, resulting in poor interfacial adhesion, [10] reduce stress transfer efficiency from the polymer matrix to the piezoelectric inclusions, and suppress the functional performance. Increasing the matrix stiffness was previously shown to be key to enhancing piezoelectric response, [11] but it remains unclear if highly-responsive flexible piezoelectric materials are possible.Recent studies have explored surface functionalization of a low concentration of BTO nanoparticles (below 2 vol%, i.e., 10 wt%) to covalently bind them to the polymer matrix, and have demonstrated appreciable enhancement of the piezoelectric coefficient 3D Printed Nanocomposi...

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