To improve fracture toughness and encourage excellent self‐crack‐healing ability, mullite/SiC particle/SiC whisker multi‐composites and mullite/SiC whisker composites were hot pressed. The crack‐healing abilities and mechanical properties of these sintered composites were investigated. Based on the obtained results, the usefulness of the mullite composite as a material for springs was discussed. The part of mullite/15 vol% SiC whisker/SiC 10 vol% particle containing healed cracks retained high reliability over the whole measured temperature range. When the crack‐healing ability was endowed by SiC whiskers alone, the parts containing the healed pre‐cracks were found to have a heat‐resistance limit temperature. Mullite/15 vol% SiC whisker/10 vol% SiC particle multi‐composite had the best potential as a material for springs used at high temperatures, because it had an adequate crack‐healing ability as well as shear deformation ability almost two times stronger than that of monolithic mullite.

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This paper reports on the development and evaluation of various probes consisting of silicon cantilevers with different types of tips made of platinum, ruthenium, chromium and conductive CVD diamond for probe-based ultrahigh density ferroelectric data storage. Using the metal-tip probes, data bits on a medium can be written and read with contact operation. Durability experiments of the various tips against a ferroelectric material are performed. The most detrimental tip wear occurred for platinum, while wear was much less apparent for the remaining tips. Reading and writing experiments on an LiTaO(3) plate are also performed on the basis of scanning nonlinear dielectric microscopy using ruthenium- and chromium-tip probes.

To enable the accurate reproduction of organs in vitro, and improve drug screening efficiency and regenerative medicine research, it is necessary to assemble cells with single‐cell resolution to form cell clusters. However, a method to assemble such forms has not been developed. In this study, a platform for on‐site cell assembly at the single‐cell level using optically driven microtools in a microfluidic device is developed. The microtool was fabricated by SU‐8 photolithography, and antibodies were immobilised on its surface. The cells were captured by the microtool through the bindings between the antibodies on the microtool and the antigens on the cell membrane. Transmembrane proteins, CD51/61 and CD44 that facilitate cell adhesion, commonly found on the surface of cancer cells were targeted. The microtool containing antibodies for CD51/61 and CD44 proteins was manipulated using optical tweezers to capture HeLa cells placed on a microfluidic device. A comparison of the adhesion rates of different surface treatments showed the superiority of the antibody‐immobilised microtool. The assembly of multiple cells into a cluster by repeating the cell capture process is further demonstrated. The geometry and surface function of the microtool can be modified according to the cell assembly requirements. The platform can be used in regenerative medicine and drug screening to produce cell clusters that closely resemble tissues and organs in vivo.

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