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Metastable c-Al xT1− xN is an important and well-established hard coating in the tool industry. To improve the mechanical and thermal properties, Al-rich c-Al xTi1− xN coatings with controllable preferred crystal orientations were fabricated via low-pressure chemical vapor deposition ( LP- CVD) in an industrial plant, using an AlCl3-TiCl4-NH3-Ar-H2 precursor system. The c-Al xTi1− xN coatings with (100)- and (111)-preferred orientations and average x values of 0.82 and 0.73, respectively, comprised c-Al(Ti)N/c-Ti(Al)N nanolamellae with average compositions of c-Al0.9Ti0.1N/c-Al0.6Ti0.4N and c-Al0.80Ti0.20N/c-Al0.50Ti0.50N; the average lamellar periods were 7.7 and 4.5 nm, respectively. High-resolution transmission electron microscopy indicated that the c-Al(Ti)N/c-Ti(Al)N nanolamellae were modulated along the <100> direction, implying coherent spinodal decomposition of c-Al xTi1− xN in the as-deposited state. The hardness of the c-Al xTi1− xN coatings varied from 33 to 36 GPa, depending on the (100)- or (111)-preferred orientation. Residual stress measurements in the as-deposited state showed tensile stress values of 1.8 and 4.6 GPa for the (100)- and (111)-oriented c-Al xT1− xN coatings, respectively. This stress may be generated by the difference in the thermal expansion coefficient of the c-Al xT1− xN coating and the carbide substrate and by coherency stress in the c-Al(Ti)N/c-Ti(Al)N nanolamellae. In situ high-temperature X-Ray diffraction results revealed high thermal stability up to 1000°C. [ABSTRACT FROM AUTHOR]

Lithium ion conductors with garnet-type structure are promising candidates for applications in all solid-state lithium ion batteries, because these materials present a high chemical stability against Li metal and a rather high Li+ conductivity (10−3-10−4 S/cm). Producing densified Li-ion conductors by lowering sintering temperature is an important issue, which can achieve high Li conductivity in garnet oxide by preventing the evaporation of lithium and a good Li-ion conduction in grain boundary between garnet oxides. In this study, we concentrate on the use of sintering additives to enhance densification and microstructure of Li7La3ZrNbO12 at sintering temperature of 900°C. Glasses in the LiO2-B2O3-SiO2-CaO-Al2O3 ( LBSCA) and BaO-B2O3-SiO2-CaO-Al2O3 ( BBSCA) system with low softening temperature (<700°C) were used to modify the grain-boundary resistance during sintering process. Lithium compounds with low melting point (<850°C) such as LiF, Li2 CO3, and Li OH were also studied to improve the rearrangement of grains during the initial and middle stages of sintering. Among these sintering additives, LBSCA and BBSCA were proved to be better sintering additives at reducing the porosity of the pellets and improving connectivity between the grains. Glass additives produced relative densities of 85-92%, whereas those of lithium compounds were 62-77%. Li7La3ZrNbO12 sintered with 4 wt% of LBSCA at 900°C for 10 h achieved a rather high relative density of 85% and total Li-ion conductivity of 0.8 × 10−4 S/cm at room temperature (30°C). [ABSTRACT FROM AUTHOR]