The need for improved functionalities in extreme environments is fuelling interest in high-entropy ceramics1–3. Except for the computational discovery of high-entropy carbides, performed with the entropy-forming-ability descriptor4, most innovation has been slowly driven by experimental means1–3. Hence, advancement in the field needs more theoretical contributions. Here we introduce disordered enthalpy–entropy descriptor (DEED), a descriptor that captures the balance between entropy gains and enthalpy costs, allowing the correct classification of functional synthesizability of multicomponent ceramics, regardless of chemistry and structure. To make our calculations possible, we have developed a convolutional algorithm that drastically reduces computational resources. Moreover, DEED guides the experimental discovery of new single-phase high-entropy carbonitrides and borides. This work, integrated into the AFLOW computational ecosystem, provides an array of potential new candidates, ripe for experimental discoveries.
Due to its outstanding electrical characteristics, such as the low temperature expansion coefficient, low dielectric constant and good mechanical properties, cordierite, 2MgO⋅2Al2O3⋅ 5SiO2, is a very attractive high-temperature ceramic material. In order to accelerate the process of sintering, 2.50 mass% Bi2O3 has been added to the starting mixtures. Liquid phase sintering caused by the presence of bismuth-oxide lowers the temperature of cordierite formation. The mechanical activation of the starting mixtures (0–56 min in vibro-mill) additionally lowers sintering temperatures. The sintering process was performed at 1200, 1300, 1350 and 1400 °C, for 2 h. The particle size analysis (PSA) was employed in order to determine the changes in the particle size of the mechanically treated powders. The phase composition of the starting powders and sintered materials was analyzed by the X-ray diffraction method. Furthermore, scanning electron microscopy (SEM) was used in the analysis of the powder morphology
Multiferroic materials attracted a lot of attention in recent years because of their significant scientific interest and technological applications. The multiferroic core/shell powders have a better connectivity between the phases, resulting in superior dielectric and magneto electric properties. In this study, the influence of preparation condition on structure and properties of BaTiO3/α-Fe2O3 core/shell composite materials was examined. The five samples were obtained by varying synthesis conditions, such as synthesized method (co-precipitation and sonochemical method) and pH values of solution. XRD and Raman spectroscopy analyses were performed in order to determine phase composition and structural changes within samples. Morphology modifications were examined by SEM and EDS analyses. Finally, effect of structural and microstructural changes on magnetic and electrical properties was detected and explained.