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This paper deals with the effects of preparation methods on the texture development and densification in textured SrBi4Ti4O15 (SBT) ceramics. The specimens were prepared by the oriented consolidation of anisotropic particles (OCAP), templated grain growth (TGG) and reactive templated grain growth (RTGG) methods. The specimens with extensive texture were obtained by all methods except for TGG with small template and large matrix particles. The origin of extensive texture development was the growth of aligned platelike particles. A characteristic of microstructure was the formation of colonies, in which platelike grains contacted face-to-face. The size of colonies was dependent on the preparation method, and determined the size of pores between colonies, which had a large effect on the sintered density. The OCAP and RTGG methods gave the green compacts composed of only platelike particles and large colonies and pores formed during sintering. The TGG method gave the green compacts composed of platelike and equiaxed particles and prevented the formation of large colonies and pores during sintering. Thus, the dense, highly-textured SBT ceramics were obtained by the TGG method. [ABSTRACT FROM AUTHOR]

This paper examines the effect of exposure to high-intensity light on the structure, thermal expansion, mechanical properties, and Raman spectrum of ceramic NbO. We demonstrate that such exposure creates fractal micro- and nanostructures in ceramic NbO, has a significant effect on its thermal expansion, increases its elastic moduli and the anisotropy in its mechanical properties, and produces isolated polyhedra in its crystal structure. [ABSTRACT FROM AUTHOR]

Natural composites are often heterogeneous to fulfil functional demands. Manufacturing analogous materials remains difficult, however, owing to the lack of adequate and easily accessible processing tools. Here, we report an additive manufacturing platform able to fabricate complex-shaped parts exhibiting bioinspired heterogeneous microstructures with locally tunable texture, composition and properties, as well as unprecedentedly high volume fractions of inorganic phase (up to 100%). The technology combines an aqueous-based slip-casting process with magnetically directed particle assembly to create programmed microstructural designs using anisotropic stiff platelets in a ceramic, metal or polymer functional matrix. Using quantitative tools to control the casting kinetics and the temporal pattern of the applied magnetic fields, we demonstrate that this approach is robust and can be exploited to design and fabricate heterogeneous composites with thus far inaccessible microstructures. Proof-of-concept examples include bulk composites with periodic patterns of microreinforcement orientation, and tooth-like bilayer parts with intricate shapes exhibiting site-specific composition and texture. [ABSTRACT FROM AUTHOR]

The effects of β-spodumene (Li2O·Al2O3·4SiO2) and zirconia additives on the physical and thermal characteristics aluminium titanate (AT) ceramics have been investigated. XRD, DTA, SEM, TEM and dilatometry have been used to characterise the influence of these additives on phase relations, densification, microstructure, thermal expansion, thermal decomposition and thermal shock behaviour of AT. The results show that the presence of both β-spodumene and zirconia significantly reduces porosity, lowers thermal expansion, improves densification, hardness and thermal stability, without degradation of thermal shock resistance. Microstructural examinations have revealed the presence of glassy phase due to the phase separation of β-spodumene and spontaneous microcracks due to thermal expansion anisotropy of AT. [ABSTRACT FROM AUTHOR]