Silica soot waste was successfully upcycled into complex structured transparent silica components by designing interparticle photo-cross-linkable slurry which is composed of small amounts of multifunctional acrylate, photo radical initiator, and silica soot modified by functionalized polyethyleneimine (PEI). After optimizing the additive contents of functionalized PEI and the ball milling time of the slurries to prepare low viscous slurries with improved silica soot dispersion, sintering conditions to achieve full densification of the photo-cured bodies was investigated. Sintering of ‍photo-cured bodies, which was prepared from 32 vol% silica soot slurries stabilized by 1.1 mg/m² of functionalized PEI, at 1350°C for 60 min resulted in successful densification to a transparent silica glass component.

Powder compression is the process of obtaining pellets by directly applying pressure to powder beds. The densification phenomenon involving the plastic deformation of particles is still unclear. In this study, the powder compression process of the binary mixture of powder with different plasticity was calculated by using the discrete element method incorporating Edinburgh elasto-plastic adhesion model. The macroscopic and microscopic powder properties were evaluated in the conditions of different volume fraction plastic powders. The calculation method of contact plasticity between elastic and plastic particles, which was proposed in this study, was validated by the data of experimental comparison tests. The result of this study indicated that particle plasticity strongly affected the powder properties, especially contact area inside the powder bed. We hope that this study will be useful for applications where the contact area inside the powder bed is important, such as batteries.

In order to give water resistance to aluminum nitride particles for preparation of ceramics using aqueous slurry, graphene coating by mechanical treatment on the particles was investigated. Graphene coating was observed on the surface of the fine aluminum nitride particles which was obtained by mechanical treatment of mixed powder of graphene and aluminum nitride in a compression and shear field. The graphene-coated aluminum nitride particles showed excellent water resistance, since the pH value of the aqueous suspension did not change and aluminum hydroxide was not detected even after stirring for long time. The relative density of the aluminum nitride ceramics obtained with the composite particles was high, and their secondary phase was also found to be yttrium aluminate having less oxygen than those prepared without graphene coating, due to suppressed hydrolysis.

This review discusses about synthesis of monolayer nanoparticles of organic–inorganic hybrid metal hydroxide salts (MHSs) and use them as building blocks to fabricate higher order structures. Epoxide-mediated basification induces high supersaturation condition, which leads formation of MHS nanoparticles. Incorporation of carboxylic acids enables tuning stability of nanoparticles, as a result, monolayer MHS nanoparticles are obtained by incorporating monocarboxylates. In the case of MHS nanoparticles including acrylate, nanoparticle-interconnected porous materials are obtained through thermal-, photo-, and self-polymerization of acrylate moiety. Electrochemical functions of MHS nanoparticles are found to be controlled by organic carboxylate moiety. Various metals, alloys, carbides, pnictides, chalcogenides, and halides can be prepared through thermal conversion of MHS nanoparticles.