Zero thermal expansion phases from the A 2 M 3 O 12 and related thermomiotic (negative thermal expansion) families are natural candidates for applications where high thermal shock resistance is the principal requirement. However, their mechanical properties are largely unknown, as are sintering routes for consolidation into bulk objects. Therefore, a preliminary case study on the effect of microstructure on mechanical strength and thermal shock resistance of Al 2 W 3 O 12 has been performed. All thermal and mechanical properties necessary for calculation of thermal shock resistance figures of merit have been measured experimentally. Tensile strengths were measured by four-point flexural test and analyzed by the Weibull method. The microstructure of bulk specimens, conventionally pressureless sintered at 1273 K, was coarse-grained, containing microcracks, and inhomogeneous with respect to density due to the agglomeration of nanoparticles, and led to low tensile strength. Despite this, thermal shock resistance features evaluated for Al 2 W 3 O 12 are encouraging. The Hasselman figure of merit for thermal shock resistance for severe heating conditions of Al 2 W 3 O 12 was 120 K, comparable to sapphire, the state-ofthe-art material for some advanced thermal shock resistance applications. This study shows that zero thermal expansion phases from the A 2 M 3 O 12 family have potential to be transformed into useful engineering ceramics for thermal shock resistance applications.

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Data revealing the phase and chemical compositions of natural black sands from “El Ostional” beach, located in the northern Ecuadorian Pacific coast have been presented. The samples were collected from six points over the shore area of approximately 500 × 40 m 2 . The data on crystalline phases (iron titanium oxide, orthoclase feldspar and zircon) were determined by X-ray powder diffraction (XRPD), while semi-quantitative chemical analyses of major (Fe and Ti) and trace elements were obtained by X-ray fluorescence spectroscopy (XRF). The phase composition was verified by scanning electron microscopy (SEM), using backscattered electron (BSE) mode and energy dispersive spectroscopy (EDS). These comprehensive data are a contribution to valorize ilmenite-hematite solid solutions from natural resources towards the identification of novel technological applications.

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This article presents several micromechanical models to predict the Young's modulus and the coefficient of thermal expansion of titanate nanotube/Y 2 W 3 O 12 /HDPE composites. The equations and assumptions of the selected micromechanical models are described in detail for this ternary system. Data of the elastic constants, coefficient of thermal expansion of composite components and other associated parameters, obtained either by literature survey or processing of literature information, are compiled in this work. For further interpretation of the data presented in this article, please see our research article entitled “The effect of titanate nanotube/Y 2 W 3 O 12 hybrid fillers on mechanical and thermal properties of HDPE-based composites” (Pontón et al., 2019).