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K+-ion substituted single crystalline BaTi2O5, Ba1−xKxTi2O5−z (x = 0 to 0.006), was prepared by floating zone method. The effect of K+-ion substitution on the electrical properties of Ba1−xKxTi2O5−z was studied using impedance spectroscopy. Ba1−xKxTi2O5−z showed ferroelectricity and ion/hole mixed conduction in the b-direction. With increasing K+ content from x = 0 to 0.006, the Curie temperature (Tc) decreased from 752 to 722 K, and permittivity decreased from 18,600 to 3970. The ionic conduction behavior (ion blocking at low frequency region) became significant by the K+ substitution showing maximum at x = 0.003. The electrical conductivity of Ba1−xKxTi2O5−z increased with increasing oxygen partial pressure, and was almost 100 times higher than that of BaTi2O5 in the temperature range of 500–650 K. The activation energy of electrical conductivity was 0.8–1.5 eV.

(Ti, Zr)(C, N) solid solutions with 10–90 mol% of ZrC were prepared by spark plasma sintering (SPS) using TiCN and ZrC powders as starting materials. The decomposition behavior of the (Ti, Zr)(C, N) solid solutions as a function of heat treatment temperature (1273–2173 K) was investigated. (Ti, Zr)(C, N) solid solutions with 20–80 mol% of ZrC were decomposed into TiCN-rich (Ti, Zr)(C, N) and ZrCN-rich (Zr, Ti)(C, N) phases when heat-treated in the temperature ranged from 1373 to 2173 K for 3.6 ks, respectively. After heat treatment, lamellar microstructure was formed with an orientation relationship of TiCN-rich (Ti, Zr)(C, N) {100} // ZrCN-rich (Zr, Ti)(C, N) {100}. The Vickers hardness and fracture toughness simultaneously increased with increasing heat-treatment temperature and showed the maximum values of 25.0 GPa and 2.5 MPa m1/2, respectively, for Ti0.5Zr0.5C0.75N0.25 at the heat-treatment temperature of 1873 K.

Herein, we report on the synergetic effect of simultaneously using of hexamethyldisilane (HMDS) and trimethylamine borane (TMAB) as precursors for a high-rate laser chemical vapor deposition of SiBCN films. The major components of obtained films were successfully controlled by deposition temperature from B4C to graphene and β-SiC. In addition, B4C and graphene/β-SiC films were synthesized from TMAB and HMDS, respectively. The growth rate of SiBCN films was extremely high (up to 1620 μm/h) in contrast to 18 μm/h and 415 μm/h for graphene/β-SiC and B4C films, respectively. Thermodynamic modeling demonstrated that reactions between nitrogen- and silicon-containing gas species during double-source CVD process could be the possible reason of synergism and growth rate increasing. A mechanical study demonstrated very high hardness (up to 43 ± 7 GPa) and wear resistivity of the SiBCN films. The reported results reveal a significant potential of precursor synergism for the design of new materials with enhanced properties.

In this study, the vapor-phase growth of lanthanum phosphate (LaPO4 monazite) films having preferred orientations on polycrystalline alumina substrates was demonstrated via laser chemical vapor deposition using metal-organic precursors. The effects of the laser power densities and oxygen (O2) partial pressure on the crystal orientations, microstructures, and textures of the LaPO4 films were investigated. Monoclinic LaPO4 monazite was grown at laser power densities of 62–96 W cm−2 (deposition temperatures of 1075–1120 K) and an O2 partial pressure of 257 Pa. The (1 1 1 ¯ )-oriented LaPO4 films with small pyramidal facets of less than 1 μ m in sizes and large platelets were grown at laser power densities lower than 85 W cm−2. The preferred orientation of the monoclinic LaPO4 changed from (1 1 1 ¯ ) to (1 0 1 ¯ ) as the laser power density was increased to 95 W cm−2, at which large platelets inclined from the substrate surface were formed. Deposition with a reduced O2 partial pressure of 200 Pa induced the growth of highly (1 1 1 ¯ )-oriented LaPO4 films with small pyramidal facets, which comprised (0 0 1), (1 0 0), and (0 1 0) faceted planes. At a low O2 partial pressure of 133 Pa, (1 0 0)-oriented LaPO4 films with platelet grains vertically grown from the substrate were formed. The deposition rates of the LaPO4 films were as high as 58.6 μ m h−1.

Ti4+ ions of the materials solidified from the BaTi2O5–Ba6Ti17O40 (BT2–B6T17) eutectic melt were substituted with 0–1.0 at% Nb5+ ions (CNb = 0–1.0 at%) by a floating zone method, and the effects of CNb on the microstructure, permittivity and Curie temperature of the BT2–B6T17 eutectics were studied. The BT2–B6T17 eutectics at CNb = 0–1.0 at% consisted of BaTi2O5 and Ba6Ti17O40. b- and a-axes of BaTi2O5 and Ba6Ti17O40, respectively, were parallel to the growth directions of the BT2–B6T17 eutectic. Ba6Ti17O40 in the BT2–B6T17 eutectic had the rod-like structure parallel to the growth direction in the matrix of BaTi2O5. As CNb increased from 0 to 1.0 at%, the permittivity at room temperature increased from 70 to 214 and the Curie temperature decreased from 748 to 679 K.

The coating of various types of materials, i.e., metals, ceramics, polymers, and composites, with ceramic layers and films is one of the key technologies employed for prolonging the lifetime of infrastructural materials by protecting them from harsh environments. This process also enhances properties and adds multi-functionalities to materials. Thermal barrier coatings (TBCs) on turbine blades, hard coatings on cutting tools, and corrosion-protective coatings on steel pipes and containers are applied on an industrial scale, while biocompatible coatings on artificial bones, growth of semiconductor films, and depositions of nano-layers and particles for catalysts have been developed to produce high-performance functional materials. Vapor-phase deposition techniques, such as physical vapor deposition (PVD) and chemical vapor deposition (CVD), are advantageous, as they create finely controlled microstructure in films and deposits, compared to liquid- and solid-state processes. In TBCs fabricated by the electron beam evaporation method, the growth of columnar crystals with nanostructures, such as nano-pores and gaps, contributes to the relaxation of thermal stress at the interface between coatings and basal materials, owing to the difference in thermal expansion coefficients. CVD, an industrially important vapor-phase deposition technique, has been employed for the growth of silicon semiconductors, thin film processing of integrated circuits, insulating coatings, and hard coatings on cutting tools. In CVD, regulation of the process parameters, such as deposition temperatures, pressures, and instrumental systems of heating and supplying precursor vapors, has enabled us to produce various types of deposits with well-controlled microstructures and unique textures. Single crystal-like highly pure films can be grown, while coatings with thick layers can be deposited. CVD is also employed for the synthesis of nanomaterials, such as graphene and carbon nanotubes (CNTs) and for the infiltration in manufacturing of fiber-reinforced ceramic composites (ceramic matrix composite: CMC). CVD techniques combined with high-power laser irradiation have enabled the fabrication of thick layers with discriminating microstructure at significantly high deposition rates. Although the typical applications of CVD techniques are for the deposition of films on flatter surfaces of plate-shaped substrates like wafers, CVD can also deposit coating layers and nanoparticles on particulate and porous substrates with complex surface configurations because of its excellent step coverage. These CVD techniques utilizing laser processing and powder technologies are expected to contribute to the further development of additive manufacturing. In this chapter, the basis of conventional CVD processing is briefly outlined; then high-speed deposition and refinements of microstructure by CVD using the auxiliary energy of high-powered lasers and the deposition of coatings and nanoparticles on particulate substrates by a rotary CVD technique are introduced.

A ZrB2–ZrN eutectic composite was prepared by arc-melting a mixture of ZrB2 and ZrN powders under a N2 atmosphere. The eutectic composition was 48ZrB2–52ZrN (mol%), resulting in a rod-like microstructure comprising hexagonally faceted ZrN single-crystal rods dispersed in a ZrB2 single-crystal matrix. The crystal orientation relationship between the ZrB2 matrix and the ZrN rod was ZrB2 $$\left\{ {11\bar 20} \right\}$$//ZrN{101} and ZrB2 //ZrN . The rod-like eutectic composite had a Vickers hardness of 16.2 GPa.

Iron disilicide (α-FeSi2) is one of the promising materials for building ohmic contacts over silicon substrates. Complex approaches have been used to synthesize this material resulting in the insufficient control of the film surface and interface structure. The morphology of the α-FeSi2 films synthesized in this work by one-step CVD technique from ferrocene varies from the highly-oriented self-assembled crystallites to the dense film of α-FeSi2. The orientation of the material could be changed from α-FeSi2(001)||Si(100) to α-FeSi2(111)||Si(100) by raising the deposition temperature from 900 to 1000 °C. The epitaxial relationships FeSi2(001)||Si(100), α-FeSi2(010)||Si(001), and α-FeSi2(111)||Si(100), α-FeSi2(11¯0)||Si(011) were determined for both orientations by a pole figure technique. It was found the surface of the material has an iron oxide admixture. Both the surface and interface structure might have a great impact on the properties of the α-FeSi2/Si structures. Keywords: α-FeSi2, Epitaxial growth, Self-assembled structures, Surface composition

La3+ ion substituted single-crystalline BaTi2O5 (Ba1−xLaxTi2O5−z) was prepared by a floating zone method, and the effect of La3+ ion substitution on the phase composition, microstructure and dielectric properties of Ba1−xLaxTi2O5−z was investigated. Ba1−xLaxTi2O5−z was a single phase of BaTi2O5 and its growth direction was parallel to the b-axis at an La3+ content lower than 0.9 at% (x 10 Hz) at an La3+ content higher than 0.4 at%, indicating the predominance of electronic conduction. The remanent polarization (Pr) of Ba1−xLaxTi2O5−z at room temperature increased with increasing x and was as high as 7 × 10−2 C m−2 at Ba0.996La0.004Ti2O5−z.

ZrCN–TiCN solid solutions were consolidated by spark plasma sintering (SPS) using ZrC and TiCN powders at 1573–2373 K for 300 s. ZrCN–TiCN solid solutions were densified to relative densities of 96–99% at temperatures above 2073 K. When sintered below 1973 K, the sintered bodies were composed of two phases, Zr-rich and Ti-rich solid-solution phases, whereas a ZrCN–TiCN solid solution in a single phase was obtained above 2073 K. With increasing the sintering temperature, the lattice parameters of the ZrCN–TiCN solid solution decreased and increased at Zr-rich and Ti-rich compositions, respectively. The ZrCN–TiCN solid solution exhibited a Vickers hardness ( H V ) of 23 GPa and a fracture toughness ( K IC ) of 3.5 MPa m 1/2 .

Zr-based ceramics are of interest for applications in aerospace propulsion, owing to their high hardness and stability. Application of these ceramics requires better understanding of their mechanical behavior in small scales and at elevated temperatures. Here, we prepared a ZrB2-ZrC ceramic eutectic composite, consisting of self-assembled ZrC rods grown within a single-crystalline ZrB2 matrix, and studied the mechanical properties of the individual eutectic phases using nanoindentation at both room and elevated-temperatures. The Vickers hardness of the eutectic composite was measured at room temperature. These data provide insight into the understanding of the mechanical behavior of the individual phases of non-oxide ceramic eutectic composites for high-temperature applications.

Forests of multiwalled carbon nanotubes (MWCNTs) were grown on the facets of synthetic diamond crystals by treating them in a rotary chemical vapor deposition reactor. Nickelocene was used as a source of both nickel catalyst and carbon for the formation of MWCNTs. The diamond crystals were not subjected to any surface treatment prior to the MWCNT growth. The MWCNTs were anchored in nickel particles adhered to the diamond facets and were partially filled with nickel. These morphological features of the diamond-MWCNT structures together with nanotube branching suggest the formation of MWCNTs by the combined growth mechanism.

Room-temperature fracture toughnesses of TiC-added Mo-Si-B alloys were evaluated for samples of three different compositions prepared using a conventional Ar arc-melting technique. The first alloy (TiCp) had a primary phase during solidification of NaCl-type TiC including an amount of Mo, with a Mo solid solution (Mo ss ) volume fraction of approximately 49% and a TiC volume fraction of approximately 19%, while the volume fraction of Mo 5 SiB 2 (T 2 ) was approximately 31% and the remaining 1% was Mo 2 C including an amount of Ti. The second alloy (T2p) had a primary phase of T 2 , with volume fractions of Mo ss , TiC, Mo 5 SiB 2 (T 2 ), and Mo 2 C of approximately 38%, 4%, 45%, and 13%, respectively. The third alloy (Mop) had a primary phase of Mo ss , with volume fractions of Mo ss , TiC, Mo 5 SiB 2 (T 2 ), and Mo 2 C of approximately 55%, 8%, 32%, and 6%, respectively. Room-temperature fracture toughness was evaluated by three different bending tests using Chevron-notched specimens. Fracture toughness values obtained by the three methods were relatively close with good reproducibility. Consequently, the fracture toughness values of TiCp, T2p, and Mop were evaluated to be ∼15.2 MPa(m) 1/2 , ∼10.5 MPa(m) 1/2 , and ∼13.6 MPa(m) 1/2 , respectively. Fracture surface observations indicated that the Mo ss phase is subject to severe plastic deformation during the fracture process. The TiC phase was also noted to leave river patterns behind through crack propagation. These fractographic results suggest that not only the ductile-phase toughening by the Mo ss phase but also an extra-toughening mechanism by the TiC phase are responsible for the goodness of the room-temperature fracture toughness of the MoSiBTiC alloys.

The BaTi2O5–Ba6Ti17O40 eutectic (BaO–68.7 mol% TiO2) was directionally solidified by the floating zone (FZ) method and crystalline phases, microstructures and orientation were investigated. Ba6Ti17O40 with faceted rod-like shape was dispersed in the BaTi2O5 matrix. The growth directions of BaTi2O5 and Ba6Ti17O40 were parallel to the b and a axis, respectively, and the orientation relations were BaTi2O5 (010)//Ba6Ti17O40 (60 2 ) and BaTi2O5 (001)//Ba6Ti17O40 (001).

Silicon carbide (SiC) layers were deposited on silica (SiO 2 ) glass powder by rotary chemical vapor deposition (RCVD) to form SiO 2 glass (core)/SiC (shell) powder; this powder was consolidated by spark plasma sintering (SPS). SiO 2 glass powder with a particle size of 250 nm was coated with 5–10-nm-thick SiC layers. The resultant SiO 2 glass (core)/SiC (shell) powder was consolidated to form a nano-grain SiO 2 glass composite at a relative density above 90% by SPS in the sintering temperature range of 1573–1823 K. The Vickers hardness and fracture toughness of the SiO 2 glass composite at 1723 K were found to be 14.2 GPa and 5.4 MPa m 1/2 , respectively.

Films composed of a mixture of Na-β- and βʹʹ aluminas (β/βʹʹ-alumina) were prepared via laser chemical vapor deposition (CVD) upon the addition of Li. The effect of the Li source gas on the phase formation, microstructure and deposition rates of the β/βʹʹ-alumina films was investigated. The Na-β/βʹʹ-alumina films were formed at a Li/Al precursor supply ratio ( R Li/Al ) of 0.1–1.0 within a deposition temperature ( T dep ) range of 1100–1220 K. The Na-β/βʹʹ-alumina phase was exclusively formed at T dep =1165–1185 K and R Li/Al =0.1–0.5, whereas α-Al 2 O 3 (with minor amounts of LiAlO 2 and LiAl 5 O 8 ) was predominantly observed at T dep >1223 K and R Li/Al >1.0. The Na-β/βʹʹ-alumina films were composed of polygonal facets in sizes of several hundred nanometers with a columnar cross section. The deposition rate of the Na-β/βʹʹ-alumina film was 60 µm h −1 .

A large-size (25 μm in diameter) diamond powder was coated with a SiC layer by rotary chemical vapor deposition. The SiC-coated diamond powder was consolidated with a SiO2 additive by spark plasma sintering (SPS) under a moderate pressure of 130 MPa at 1673–1973 K for 300 s. The relative density of the diamond body with 35 wt% SiO2 using the SiC-coated diamond powder was in the range 98–99% while that of the uncoated diamond powder was in the range 89–94%. The highest Vickers hardness of the SiC-coated diamond bodies was 36 GPa at 4.9 N.

Zr4+-substituted single crystalline BaTi2O5 (Ba(Ti0.99Zr0.01)2O5) was prepared by the floating zone method, and its dielectric properties were investigated. The growth direction of Ba(Ti0.99Zr0.01)2O5 was parallel to the b axis. The Curie temperature of Ba(Ti0.99Zr0.01)2O5 was 710 K, which was 42 K lower than that of BaTi2O5. The complex impedance plane plot of BaTi2O5 in the b direction showed a semicircle associated with ferroelectric response and a spike associated with ionic conduction at 623 K. On the other hand, the complex impedance plot of Ba(Ti0.99Zr0.01)2O5 showed a single semicircle, suggesting almost no ionic conduction. The electrical conductivity of Ba(Ti0.99Zr0.01)2O5 was approximately half of that of BaTi2O5.

Electrical properties of single-crystalline BaTi 2 O 5 , prepared by a floating zone method, were examined by AC impedance spectroscopy at frequencies of 10 −2 to 10 6 Hz at temperatures of 425–970 K. Complex impedance in a direction perpendicular to (001) was exhibited by a single resistor ( R )–capacitor ( C ) parallel circuit. In the direction perpendicular to (010), four R – C parallel circuits were involved: two R – C circuits were associated with a strong temperature-dependent ferroelectric response and a slightly temperature-dependent paraelectric response, while the other two R – C circuits corresponded to the interface phenomena associated with ionic conduction. The electrical conductivity in the direction perpendicular to (010) was one-to-three orders of magnitude higher than that in the direction perpendicular to (001).

Cobalt oxide (Co3O4) catalysts supported on α-Al2O3 were prepared by a rotary chemical vapor deposition (CVD) method. Although the specific surface area of α-Al2O3 powders was extremely low, finely dispersed nanoparticles of Co3O4 with the size of several nanometers were formed on the support under the deposition condition of 370 °C for 30–120 min. Despite the minimal Co3O4 content of 0.10–0.36 wt%, the Co3O4/α-Al2O3 exhibited the significant catalytic activity for CO oxidation; the temperatures at which the conversion of CO reached 20% (T20) were 157–189 °C and the conversion reached 100% until 300 °C. Thus, a rotary CVD method can finely control the dispersibility of Co3O4 on α-Al2O3 surface, which was related to high catalytic activity.

Dielectric properties of single-crystalline BaTiO3 in the direction to were investigated by impedance spectroscopy. The complex plane plots showed high- and low-frequency semicircles and an i...

β- SiC films were prepared on AlN substrates by laser chemical vapour deposition (LCVD) using a diode laser and hydrido-polycarbosilane as a precursor at different vacuum degrees. The effect of the vacuum degree on the orientation and the microstructure of the β- SiC films was investigated. The preferred orientation of β- SiC films shifted from (111) to (311), the surface morphologies changed from faceted to rectangular and the columnar cross-section became thicker while increasing the vacuum degree from 0.4 to 7 KPa. The high deposition rate ranged from 180 to 240 µm/h.

TiC–ZrC solid solutions at ZrC composition of 5–90 mol% were consolidated by spark plasma sintering of TiC and ZrC powders. The phase decomposition behavior by heat-treatment at 1273–2273 K was investigated. TiC–ZrC solid solutions with 10–70 mol% ZrC decomposed into TiC- and ZrC-rich phases after heat treatment at 1473–2273 K for 3.6 ks. The decomposition resulted in the formation of nodular structures several tens to hundreds nanometers in length with coherent crystal orientation relationship of the TiC-rich phase {100} // ZrC-rich phase {100}. The Vickers hardness and fracture toughness increased with increasing heat-treatment temperature and reached maximum values of 26 GPa and 3.0 MPa m1/2, respectively, for 80TiC–20ZrC heat treated at 1873 K.

Nb5+-substituted single-crystalline BaTi2O5 (Ba(Ti1−xNbx)2O5+z) was synthesised by a floating zone method, and the effect of Nb5+ substitution on the dielectric properties of Ba(Ti1−xNbx)2O5+z was investigated. The growth direction of Ba(Ti1−xNbx)2O5+z was parallel to the b axis. The a lattice constant and β angle increased from 1.6906 to 1.6918 nm and from 103.09° to 103.13° at x=0–0.7 at%, respectively. With increasing x, the Curie temperature of Ba(Ti1−xNbx)2O5+z decreased from 750 to 652 K. A complex impedance plane plot of BaTi2O5 at 598 K in the b direction showed a semicircle at high frequencies and a spike inclined at 45° to the real axis at low frequencies, indicating ionic conduction of bulk BaTi2O5. At x>0.002 (0.2 at%), the complex impedance plots of Ba(Ti1−xNbx)2O5+z showed no inclined spike, suggesting dominantly electronic conduction. The electrical conductivity of Ba(Ti1−xNbx)2O5+z increased with temperature with an activation energy of 1.4 to 1.7 eV and was minimum at x=0.001 (0.1 at%). The spontaneous polarisation of Ba(Ti0.998Nb0.002)2O5+z was 2.7×10−2 C m−2, which was 2.5 times higher than that of BaTi2O5.

A high-hardness diamond-based composite was synthesized by spark plasma sintering (SPS) under 100 MPa, using SiC-coated diamond powder prepared via chemical vapor deposition (CVD). SiC layers 20–40 nm were uniformly deposited on diamond powders by a rotary CVD technique. The SiC-coated diamond powder was consolidated with SiO2 powder by SPS at the sintering temperature of 1873 K, resulting in the formation of fully compacted mosaic microstructure with the Vickers hardness of 36 GPa.

Sodium beta alumina (Na-β-alumina) films were synthesized by heat treatment of NaAl6O9.5 and γ-NaAlO2 films at temperatures of 1 373-1 573 K. Single-phase γ-NaAlO2 and NaAl6O9.5 films were prepared by laser chemical vapor deposition at the deposition temperatures of 976 and 1 100 K, respectively. Subsequent heat treatment of the films resulted in the formation of Na-β-alumina with α-Al2O3 at temperatures above 1 373 K for NaAl6O9.5 and 1 473 K for γ-NaAlO2. On heat treatment at temperatures of 1 473-1 573 K, the faceted morphology with terraces of the as-deposited (110)-oriented γ-NaAlO2 films transformed to a porous morphology with platelet grains comprising Na-β-alumina and α-Al2O3. On heat treatment at temperatures of 1 373-1 473 K, the pyramidal, faceted grains of as-deposited NaAl6O9.5 films transformed to planer, shapeanisotropic morphology in the film of mixed Na-β-alumina and α-Al2O3. A dense morphology was observed in both the as-deposited and heat-treated NaAl6O9.5 films.

A 90TiC–10ZrC (mol%) solid solution was consolidated by spark plasma sintering at 2373 K and decomposed into Zr0.94Ti0.06C nodules and Ti0.97Zr0.03C matrix by heat treatment at 1573 K. The Zr0.94Ti0.06C nodules were precipitated in the Ti0.97Zr0.03C matrix with Ti0.97Zr0.03C {100} // Zr0.94Ti0.06C {100}. The Vickers hardness and fracture toughness increased with increasing heat treatment time up to 36 ks and exhibited the maximum values of 25.9 GPa and 3.3 MPa m1/2, respectively.

It is well known that some cerate based or zirconate based perovskites exhibit proton (H+) conduction at around 600oC [1], and those proton conducting perovskites are expected to be used as electrolyte of proton ceramic fuel cells (PCFCs). Especially, Y-doped BaZrO3 (BZY) has received attention, owing to its higher H+ conductivity than other proton conducting perovskites. However, the densification of BZY basically needs high temperature above 1400oC, leading to a critical problem when the BZY film was prepared on a Ni-based composite electrode; BZY significantly reacts with Ni and forms impurity phase such as BaY2NiO5 during the high temperature sintering [2]. In addition, this impurity phase easily decomposes under H2 atmosphere and causes the critical damage for the cell. D. Han et al. have reported that the BaY2NiO5 impurity phase disappears by heating above 1500oC [4]. However, they also have reported that Y2O3 alternatively appears in the high temperature heating [4]. Thus, a preparation technique that can fabricate thin film at lower temperature, is favorable to avoid the formation of the impurity phase in the case of BZY. Currenlty, the pulse laser deposition (PLD) method has been commonly utilized for the lower temperature deposition of ceramic thin films. However, in the case of PLD, its deposition rate is usually 1 μm/h and its area is several cm2 at best, that is, PLD has a difficulty for the practical use. Besides the PLD method, the laser chemical vapor deposition (LCVD) method, which combines a chemical vapor deposition and laser irradiation, has been proposed as one of the low temperature deposition methods. Recently, Goto et al. have demonstrated the laser chemical vapor deposition of the ceramic thin films at a lower temperature [5,6], and actually, they reported the high-speed deposition of TiN film at several 10 μm/h at 600oC- 800°C [5]. In addition, they demonstrated LCVD on a curved surface and a large surface area [6]. Thus, in this work, the preparation of the BZY film was investigated by using LCVD. The deposited BZY film was characterized by XRD, SEM and EDX, and its properties such as structure and chemical composition were analyzed in detail. As a result, it was revealed that the uniform BZY thin film with columnar structure was successfully deposited by the LCVD method. In addition, the thickness of the BZY film was about 16 μm even though its deposition time was only 10 min, suggesting the high speed deposition of BZY film is possible by using the LCVD. [1] H. Iwahara, T. Esaka, H. Uchida, N. Maeda, Solid State Ionics 3/4 (1981) 359-363. [2] L. Bi, E. Fabbri, Z. Sun, E. Traversa, J. Electrochem. Soc. 158 (2011) B797-B803. [3] S. Fang, S. Wang, K. S. Brinkman, Q. Su, H. Wang, F. Chen, J. Power Sources 278 (2015) 614-622. [4] D. Han, Y. Otani, Y. Noda, T. Onishi, M. Majima, T. Uda, RSC Adv. 6 (2016) 19288-19297. [5] Y. S. Gong, R. Tu, T. Goto, J. Alloys Compd. 485 (2009) 451-455. [6] T. Goto, SOKEIZAI 51 (2010) 20-25.

This study investigated the preparation of an Y-doped BaZrO3 (BZY) thin film electrolyte by a laser chemical vapor deposition (LCVD). The structure, chemical composition, and other properties of the deposited BZY film were analyzed in detail by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. These analyses revealed that a uniform BZY thin film consisting of columnar structures was successfully deposited by the LCVD method. In addition, the thickness of the BZY film was about 16 μm, even though the deposition time was only 10 min, indicating that high-speed deposition of the BZY film was achieved by the LCVD method.

Ceramic eutectics are naturally occurring in-situ composites and can offer superior mechanical properties. Here, ZrB2–ZrCxN1−x quasi-binary ceramic eutectic composites were produced by arc-melting a mixture of ZrB2, ZrC, and ZrN powders in an N2 atmosphere. The arc-melted ZrB2–ZrCxN1−x composites containing 50 mol% of ZrB2 (irrespective of the ZrC/ZrN ratio) showed rod-like eutectic structures, where ZrCxN1−x single-crystalline rods were dispersed in the ZrB2 single-crystalline matrices. Multiple orientation relationships between the ZrCxN1−x rods and the ZrB2 matrices were observed, and one was determined as ZrB2 { 01 1 ¯ 0 } //ZrxN1−x {111} and ZrB2 //ZrCxN1−x . The rod-like eutectic composites had higher hardness than the hypo- and hypereutectic composites and the 50ZrB2–40ZrC–10ZrN (mol%) eutectic composite showed the highest Vickers hardness (Hv) of 19 GPa.