We reviewed the current research on carbide-derived carbon (CDC) for tribological applications. Carbon materials have been produced using CDC synthesis, in which the metallic components of carbides are selectively etched using high-temperature chlorination. The CDC materials show superior material properties for various applications. SiC is the most widely used carbide, so it was the main focus of the discussion. CDC films show various synthesis-parameter-dependent crystal structures, which affect the mechanical and electrical properties. We discussed the effects of CDC synthesis parameters including adding hydrogen, choosing an appropriate reaction temperature, using catalysts, and modifying the substrate surface with a gradient carbon layer on the structures and tribological properties of CDC layers. The reactions between chlorine gas and the metal components of carbides require the proper reaction temperature because the bonding strengths of carbide materials are unique. CDC-synthesized carbon materials show excellent mechanical and physical properties, which can be continuously enhanced by innovatively modifying various synthesis parameters and by combining CDC materials with other materials. Therefore, CDC materials show great potential for being used in a broader range of applications, and they may lead to new and extended applications for ceramic materials.

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The influence of phenylalanine as a dispersant on the viscoelastic properties of alumina suspensions at pH 7.0 was examined in the temperature range from –100°C to +100°C. Only a small amount of phenylalanine, with both NH₃⁺ and COO^– groups present in each molecule, was adsorbed onto the positively charged alumina surfaces at room temperature. The peaks of the storage modulus and loss tangent, which were associated with the colloidal phase transition from a dispersed state to a flocculated state, were observed in 10 vol % suspensions in 39–62°C temperature range. The addition of a small amount phenylalanine enhanced the dispersibility of alumina particles and suppressed the colloidal phase transition. In the concentrated 20–30 vol % alumina suspensions containing phenylalanine, no phase transition was evident in the storage modulus or loss tangent measurements of the suspension upon heating. The addition of phenylalanine to the concentrated suspensions drastically reduced the apparent viscosity at room temperature.

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Calcium phosphate cement with a silicate ion releasing ability was prepared using a paste of α-tricalcium phosphate and a trace amount of calcium silicate hydrate gel with distilled water as a liquid phase. Hydroxyapatite formed via an amorphous calcium phosphate by adding calcium silicate hydrate gel. The existence of calcium silicate hydrate gels influenced on the amount, crystalline size and chemical composition of the formed hydroxyapatite. The Formation of hydroxyapatite and amorphous calcium phosphate led to developing the compressive strength of the cement after the solidification. The incorporation of less than 0.5 mass % calcium silicate hydrate gel into the α-tricalcium phosphate paste induced silicate ion release in the cement in Tris-buffer solution.

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We have evaluated the morphology dependent biological behaviors of calcite particles in simulated body fluid conditions. Two kinds of calcite particles with different morphologies (cubic and spicule) were prepared utilizing different polyol solvents. According to X-ray diffraction, scanning electron microscopy, zeta potential measurement and dynamic light scattering study, two calcite samples had different morphology but other physicochemical parameters like particle size and surface chemistry of two samples were similar. The biological behaviors of two calcites were evaluated in simulated gastric and intestinal condition considering the oral administration of calcite as potential bio-medical applications. Calcium dissolution rate, change in zeta potential and interaction with proteins of differently shaped calcites in simulated biological conditions were evaluated. Spicule shaped calcites showed facilitated surface calcium ion dissolution compared with cubic shaped one in simulated gastric condition. The zeta potential measurement and protein fluorescence quenching assay results revealed that the spicule calcites interacted more actively with biological substances like electrolytes and proteins than cubic shaped one. Scanning electron microscopic images of calcites treated in simulated body fluid exhibited that the biological behaviors of calcites could be mainly determined by the dissolution and particle-biosubstance interaction at the surface of calcite particles.

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A catalytic combustion-type carbon monoxide gas sensor was fabricated by employing a Pt-loaded cerium oxide–zirconium oxide–zinc oxide solid solution as the oxidizing catalyst. Since the present catalyst can completely oxidize CO at temperature as low as 25°C. As a result, the sensor with this catalyst exhibits superior performance for the CO detection at 60°C, a temperature which is substantially lower than that (>400°C) required for the operation of sensors with the conventional CO oxidation catalyst of Pt/Al₂O₃ or Pd/Al₂O₃.

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The hybrid electrolyte (HE) was prepared through the mixing of cation-exchanged polymer and ceramic electrolyte material for providing a certain flexibility to solid electrolyte (SE). To adequately utilize features of the HE with valuable ion conductivity, the electrolyte particles should be uniformly mixed with the polymer in the HE. To do that, the mixing was performed in an aqueous solution. The elasticity and hardness of each film prepared were slightly improved by increasing the contents of the electrolyte material. The ion conductivity of the HE showed the similar value with that of the pristine SE in spite of the addition of the polymer in a high level of 97.5 wt.%, resulting from the peaceful mobility of ion through the polymer, indicating that the electrolyte particles were uniformly dispersed in the polymer. As a result, the HE could be applicable to a flexible SE in a secondary battery.

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The structural and electrical properties of mesoporous La_0.7Sr_0.3MnO₃ (LSMO) films for electrode applications were investigated as a function of annealing temperature. Mesoporous LSMO films were successfully synthesized by using sol–gel and evaporation-induced self-assembly processes. Metal acetates and Brij-S10 were used as the starting material and pore structure-forming template, respectively. With the adoption of mesoporous structure in the LSMO film, the surface area of mesoporous LSMO films was increased up to 165% with an annealing temperature increase from 350 to 650°C. The electrical conductivity value of mesoporous LSMO was determined to be 46 S/cm at a measurement temperature of 500°C. This greatly increased the surface area and provided reasonable electrical conductivity, which makes mesoporous LSMO films suitable as electrode materials of micro-solid oxide fuel cell devices.

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Synthesis of c-axis grown β-Ni(OH)₂ was attempted by rapid hydrolysis and/or direct hydrothermal treatment of the mixed solution of NiCl₂, HCl and NH₃. The UV–vis spectra revealed the addition of NH₃ into NiCl₂ solution shifted the peak position to shorter wavelength, indicating the formation of nickel ammine complex. Hydrolysis of the mixed solution containing nickel ammine complex gave β-Ni(OH)₂ particles. The amount of NH₃ in the mixed solution did not affect the crystallinity or morphology of the β-Ni(OH)₂ particle by the conventional rapid hydrolysis. Hydrothermal treatment of the hydrolyzed β-Ni(OH)₂ particles was changed the morphology from agglomerated particles to nanosheets-linked structure or hexagonal plates. However, any crystal growth or particular-axis growth was not recognized. Then, the direct hydrothermal treatment of the mixed solution was attempted. The direct treatment at certain amount of coexisting NH₃ gave small amount of the precipitates, and the precipitates showed distinctive XRD pattern of c-axis grown β-Ni(OH)₂. The electrochemical property of the c-axis grown β-Ni(OH)₂ structures indicated that the diffusion control was the rate-determining step for the charge/discharge process.

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It was demonstrated that flake-like structures containing Si-based nanosheets were successfully synthesized on Si(111) substrates. By exposure of CaSi₂/Si substrates to CrCl₂ vapor, Ca atoms were extracted from CaSi₂, then, the Si-based nanosheets were formed. The structural properties of the Si-based nanosheets formed at the edge of the flakes were examined. It is noted that the flake-like structures were rooted to the substrates, and that the Si-based nanosheets were easily exfoliated from the flake-like structures, to expose the surfaces corresponding to the Si{111} planes of the nanosheet, originated from the corrugated Si(111) layers linked by Ca in CaSi₂.

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La_0.7−xGd_xSr_0.3MnO₃ (LSGMO: x = 0.1, 0.3, and 0.5) perovskite manganite thin films were formed on a Pt(111)/Ti/SiO₂/Si(100) substrate heated to 500°C using a radio frequency magnetron sputter. The effects of substituted Gd³⁺ on the physical, chemical, and electrical properties of perovskite manganite thin films were systematically investigated. X-ray diffraction results showed that the crystallinity of the films was affected by the substitution of La³⁺ with Gd³⁺ ions. Raman spectroscopy analysis showed an increase in both the tilt of the MnO₆ octahedron and the structural distortion as a result of Gd³⁺ substitution. This is due to the increased structural instability of LSGMO associated with the rhombohedral structure, which can be contrasted with a stable crystalline structure of Gd_0.7Sr_0.3MnO₃ such as orthorhombic. From the above analyses, it was revealed that structural distortion, crystallinity, and bond strength could affect on resistive switching property.

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The stability and reactivity of phosphate raw materials, including two water-soluble phosphates, ethylene glycol-conjugated phosphate (EG-P), and polyethylene glycol-conjugated phosphate (PEG-P) developed by our group, were examined with the aim of synthesizing phosphates with high functionalities. EG-P was found to gradually hydrolyze in an aqueous solution, resulting in the formation of H₃PO₄, while PEG-P was stable for more than two months. EG-P and PEG-P did not form insoluble materials in aqueous solution in the presence of many other cations, while precipitates were often observed using conventional phosphate raw materials. In particular, there were no precipitates in an aqueous solution of PEG-P in the presence of Ca²⁺ and Li⁺ ions, which easily formed insoluble phosphates in a given aqueous condition. Consequently, single-phase LiCaPO₄ with high luminescence properties could be obtained by a polymerizable complex method employing PEG-P, while impurity phases were formed using other P sources, and KSrPO₄ was formed as a single phase using EG-P and PEG-P.

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The synthesis of oxyfluoride solid solutions with the composition (Ca_1−xSr_x)₄Si₂O₇F₂ is reported in this study. (Ca_1−xSr_x)₄Si₂O₇F₂ is found to form a solid solution within the entire composition range. Synthesis of Sr₄Si₂O₇F₂, which is the first compound in the Sr–Si–O–F system, can be regarded as one of the interesting results of this study. The Eu²⁺-activated (Ca_1−xSr_x)₄Si₂O₇F₂ solid solutions, except for Sr₄Si₂O₇F₂ exhibited photoluminescence under excitation at 300–450 nm at room temperature. The samples with x = 0.25–0.75 showed a broad red emission band with a peak around 630 nm, whereas the Ca₄Si₂O₇F₂:Eu²⁺ (x = 0) showed blue emission with a peak at 470 nm. Thus, the substitution of Sr for Ca in Ca₄SiO₇F₂:Eu²⁺ changed the photoluminescence properties remarkably.

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Nowadays a lot of studies were conducted to improve electronic properties of ZnO for transparent conducting oxide materials using single-wall carbon nanotube (SWCNT). In this study, ZnO nanocomposite films containing 0.1 wt % of SWCNTs were synthesized using a sol–gel method. Variation in ball-milling time of SWCNTs up to 12 h was introduced to induce a difference in the distribution size and length of SWCNTs. The ball-milling effect was analyzed with scanning electron microscopic studies and electrical property measurement of SWCNTs-incorporated ZnO nanocomposite films. Dispersion and shortening of SWCNTs were observed with increasing ball-milling time: dispersion was saturated but shortening was proceeded. 9 h of ball-milling time was found to optimize dispersion and shortening of SWCNTs, confirmed from the electrical property measurement. With optimized ball-milling time of 9 h, a transmittance in the visible light range of SWCNTs-incorporated ZnO film maintained over 87% of transparency. Also the resistivity of this film (0.53 Ω cm) was less than that (1.48 Ω cm) of SWCNTs-incorporating ZnO without a ball-milling.

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Ti–Si–N hard coatings have been fabricated at different N₂/Ar gas ratio (N₂:Ar = 1:1, 1:2, or 1:3) sputtering conditions by the hybrid Physical Vapor Deposition (PVD) method, which consists of sputtering and arc ion plating (AIP). The pure silicon and titanium targets were selected for reactive sputtering and the AIP process, respectively. Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray Spectroscopy (EDS) analysis has shown that the Ti/Si ratio increased as the Ar gas flow rate increased. Moreover, it found that the main growth plane of Ti–Si–N film was changed from (111) plane to (220) plane with increasing Ar gas flow from the results of X-ray diffraction (XRD) analysis. The wear rate of composite films was found to be lower than that of monolithic TiN with different friction coefficients at the initial running-in stage.

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Four sedimentary clays for Karatsu ware which were geologically derived from the weathered sandstone and granite were mined and used in this study. The chemical composition, mineral composition and morphology of minerals were investigated by XRF, XRD, SEM and TEM analysis. The mineral composition of normative α-quartz, feldspar and kaolin of two clays were 43.1, 4.7, and 44.3, and 52.1, 21.3, and 27.0, respectively. These clays had lower content of feldspar and higher content of kaolin than those of clays prepared from some sandstone for Karatsu ware. Average size of coarse particles in four clays was 22–28 µm and maximum particle size were 188–290 µm, and these sizes were similar to those of clays prepared from sandstone. It was suggested that the decomposition of feldspar to sericite and kaolin was promoted by the weathering and hydrolysis of sandstone or granite.

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Nanopowder of MgFe₂O₄ was prepared from an organic acid complex method. Among three kinds of organic acids examined, it was found from an XRD measurement that the highest purity powder of MgFe₂O₄ was obtained from a malic acid complex. SEM observation revealed that the powder is fluffy aggregates and each particle has irregular shape. The TG–DTA and IR measurements show that thermolysis process of a malic acid complex in air was mainly constructed at two stages consisting of dehydration and ligand pyrolysis. Furthermore, it was confirmed from a VSM measurement that the saturation magnetization of MgFe₂O₄ nanopowder is much smaller value than that of the bulk material.

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Rudimental research progress of oxyapatite-type rare-earth silicates is reviewed based on the published papers mainly from 1959 to 1993 that have not yet been discussed in detail. The knowledge of oxyapatite-type rare-earth silicates significantly increased during this period. Chemical compounds of rare-earth oxides and silica were discovered around 1960. Because of the complex chemical composition of the oxyapatite phase, the composition was initially considered as 2RE₂O₃·3SiO₂, which was called orthosilicate. “RE” is the rare-earth elements. Different compositions of 2RE₂O₃·3SiO₂ have been proposed by crystal structure analysis based on the crystal chemistry and the leaping model. With respect to crystal structure analysis, knowledge has gradually improved step-by-step, including the implicit distinction between oxygen-stoichiometric apatite and oxygen-deficient apatite. Based on the published work, the rare-earth silicate oxyapatites are considered to have an apatite-like structure. Initially, application research focused on the optical properties of oxyapatite because rare-earth metals were constituent elements of the crystals, and on the use of oxyapatite as a stabilizer of unwanted radioactive waste produced in nuclear power reactors because oxyapatites can dissolve the actinide elements.

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Phosphorus-substituted tobermorite was easily synthesized by hydrothermal treatment using phosphorus-doped calcium silicate hydrate as a starting material. The crystalline phase of phosphorus-substituted tobermorite was identified by X-ray diffraction pattern analysis. The diffraction patterns of phosphorus-substituted tobermorite showed good agreement with the powder patterns in tobermorite. The single phase of tobermorite was confirmed. With increasing P/(P+Si) molar ratio, the lattice constants, i.e., the a and c-axis distances, of phosphorus-substituted tobermorite decreased. A maximum P/(P+Si) molar ratio of 0.10 was incorporated in the structure of tobermorite. Increasing the P/(P+Si) molar ratio was confirmed by the adsorption bands of HPO₄²⁻ and PO₄³⁻ groups by infrared adsorption measurement. The morphology was observed by scanning electron microscopy. The primary particles were thin plate-like crystals of about 0.1 µm (thickness) × 1.0 µm (width). The secondary particles were formed into approximate spheres of about 20 µm in size by aggregation of the thin plate-like crystals.

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In this study, a double-layer thermal barrier coating was designed and deposited by an electron beam physical vapor deposition technique. The microstructure was controlled by using different target ingots during the electron beam physical vapor deposition process. The double layer coating consists of Gd₂Zr₂O₇ for the top layer and YSZ for the bottom layer. The microstructure, hardness, and thermal shock properties of the double layer deposited using a single-ingot process were compared with the results obtained with the two-ingot process. The single-ingot process involves forming the Gd₂Zr₂O₇/YSZ double layer using a single YSZ/Gd₂Zr₂O₇ double-layered ingot. The two-ingot process involves coating with each of the YSZ and Gd₂Zr₂O₇ ingots. While the XRD results indicated that the same pyrochlore-fluorite structures are formed in those ingots, differences in the microstructure and composition were observed by FE-SEM and EDS analyses. These differences influence the hardness and thermal shock resistance of the coating. The results indicate that the finer singular columns produced by the two-ingot process do not improve the hardness, but delay the delamination of the top layer during thermal shock tests due to residual compressive stress and strain tolerance.

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Microspheres consisting of WO₃ nanoplatelets were prepared by a simple polyol process using tungsten chloride, poly(vinylpyrrolidone) (PVP), and ethylene glycol. The microsphere sizes could be easily controlled by the appropriate adjustment of the molecular weight of the added PVP from 3500 to 1300000. The microspheres prepared by using PVP with a molecular weight of 1300000 had average diameters of about 877 nm and consisted of nanoplatelets that were ∼500 nm long by 30 nm wide. The gas-sensing properties of the WO₃ microspheres were investigated by exposure to 50 ppb to 1 ppm NO₂. The sensor element constructed with microspheres composed of the PVP with a molecular weight of 1300000 showed a higher sensor response to NO₂ gas than the others, because the nanoplatelets had smaller particle sizes and larger specific surface areas.

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Vaterite is a crystalline polymorph of calcium carbonate that exhibits low stability in comparison with the other crystalline polymorphs of calcium carbonate. It often assumes a spherical shape. The physical properties of vaterite are utilized in advanced biomaterials such as drug delivery systems (DDSs). The potential application of vaterite in DDSs demands a comprehensive understanding of its dissolution rate as a function of PO₄ concentration. Using in situ optical studies, we analyzed the dissolution behavior of vaterite in a simulated PO₄-containing biogenic environment. The varying physicality (i.e., the pseudo-physiological conditions) of vaterite were investigated using high-resolution cryogenic transmission electron microscopy and small-angle X-ray scattering. In addition, we measured the PO₄/Ca ratio in each part of vaterite spherulites using field-emission scanning electron microscopy in conjunction with energy-dispersive X-ray spectroscopy and inductively coupled plasma atomic emission spectrometry.
We categorized the vaterite spherulites into three parts—the shell, mantle, and core parts—on the basis of their dissolution behavior and PO₄ response. The PO₄ response to the dissolution dynamics increases toward the outer part, although the adsorption rate decreases in the presence of PO₄ and PO₄ fluorescence materials. The composition of the shell part was nearly identical to that of ideal vaterite, whereas the inner part exhibited a high C/Ca ratio and a poorly crystalline phase referred to as vaterite-like material. The dissolution rate of each part was 0.23–1.58 nm/s (shell), 0.63–3.19 nm/s (mantle), and 1.38–5.71 nm/s (core). The vaterite and vaterite-like materials were further identified according to their composition and particle size distribution.

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In order to study the combined effect of aerodynamic heating, pneumatic pressure and external constraint on the thermal shock resistance (TSR) of ZnS wave-transparent ceramic in its actual service process, the theoretical model is established by introducing the analytical solution of transient heat conduction problem of ZnS plate under aerodynamic heating into its thermal stress field model. The numerical simulation is also conducted not only to examine the theoretical model, but also to study how to improve the TSR. The influences of constraint and pneumatic pressure are studied and the effects of loosing constraint and active cooling are focused on. The study shows that the critical rupture temperature difference of simply supported ZnS plate will form wave peak; the TSR of ZnS plate is obviously optimized when loosing constraint method has been adopted, and the effect of pneumatic pressure on TSR is closely related to the change of failure region; active cooling is an effective way to improve the TSR of ZnS plate and the stronger pneumatic pressure, the better TSR, but active cooling can’t be too violent.

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Large sapphire crystals for 200-mm LED wafers were successfully grown by the top seeded melt growth (TSMG) method. The sapphire had excellent crystallinity as LED substrates. However, in the as-grown crystal, there was remarkable absorption in UV region caused by the F-center (V^×_O). To reduce the absorption, we studied several heat treatment methods using oxidized atmospheres. In air or O₂ atmospheres, the absorption was difficult to reduce because oxygen diffusion was slow and new absorption occurred. We found that heat treatment in an H₂–O₂ combustion flame was highly effective in reducing the absorption in the UV region. After the combustion flame heat treatment, the sample had an absorption coefficient less than 0.5 cm^–1 at 200 nm, and no photoluminescent emissions were caused by color centers. Consequently, sapphire crystals grown by the TSMG method had good crystallinity and low absorption in the UV region.

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Dense and transparent Y₂O₃:Eu³⁺ films were prepared by the sol–gel process and dip-coating technique from an yttrium 2–4 pentanedionate, europium nitrate and a methanol solution modified with F127 pluronic acid, by incorporation of acetic acid as pH modifier and acetylacetone as sol stabilizer. It was evaluated the effect of the F127/Y molar relationship (0, 0.1, 0.2, 1.0, 1.2 and 5.0) on the structure and photoluminiscent properties of the derived thin films. After 3 dipping-cycles, XRD results showed that the F127-modified films began to crystallize at 600°C into the cubic structure, and from 800°C, was found that the presence of F127 changes the preferential orientation from a ⟨100⟩ orientation, for the non-modified sample, to a ⟨111⟩ orientation, for the modified ones. M-lines spectroscopy characterization showed that the maximum thickness of the films modified and annealed at 900°C was 1937 nm (ρ = 4.87 g cm⁻³, η = 1.887), compared with the 881 nm (ρ = 4.94 g cm⁻³, η = 1.907) for a non-modified sample. Differential thermal analysis (DTA) and infrared spectroscopy (FTIR) were carried out to evaluate the chemical and structural evolution of the xerogel formed during the annealing process. AFM micrographs showed smooth crack-free surface (Ra = 9.2 nm) on a F127/Y = 0.2 sample. Finally, the films presented a typical Eu³⁺ reddish emission at 611 nm (D_o → ⁷F₂), which was analyzed as function of the F127 pluronic content and the annealing temperature.

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[(Mg_1–xZn_x)_0.95Co_0.05]_1.02TiO_3.02 ceramics were fabricated using solid-state synthesis for mobile communications. Zn²⁺ and Co²⁺ substitution enhanced the Qxf value and allowed densification sintering at lower temperature compared to that for [(Mg_1–xZn_x)_0.95Co_0.05]_1.02TiO_3.02, which must be sintered at 1175°C. [(Mg_0.6Zn_0.4)_0.95Co_0.05]_1.02TiO_3.02 sintered at 1175°C has a dielectric constant of 20.1, a Qxf value of 280,000 GHz, and a τ_f value of –64.7 ppm/°C. The maximum quality factor multiples resonant frequency (Qxf) value of around 280,000 GHz was obtained for the [(Mg_0.6Zn_0.4)_0.95Co_0.05]₂TiO₄.

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Recently porous ceramic membranes have received great interest due to their outstanding thermal and chemical stabilities. In this paper, we investigated whether we could prepare an alumina coating to be deposited over a diatomite-kaolin composite support layer to reliably tailor the permeability by controlling the heat-treatment temperature of the alumina coating. The pore characteristics of an alumina coating on a diatomite-kaolin composite support layer were studied by scanning electron microscopy, mercury porosimetry, and capillary flow porosimetry.

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This article has been retracted at the request of the author.

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We synthesized the lithium-tetragermanate (Li₂Ge₄O₉) phase doped with Mn⁴⁺ by glass-ceramics technique using the stoichiometric glass-precursor with different MnO₂ concentrations, i.e., 20Li₂O–80GeO₂–xMnO₂ (x = 0.1–0.7), and examined their photoluminescent property. The doped phase showed clear red-emission at room temperature, and the internal quantum-yield was found to be approximately 40% in the samples with x = 0.1–0.3.

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Phase-pure perovskite-type SrTiO₃, CaTiO₃ and BaTiO₃ electrodes have been applied for dye-sensitized solar cells, to obtain higher V_OC than TiO₂ electrode. Furthermore, TiO₂/SrTiO₃ and TiO₂/BaTiO₃ composite electrodes have been also prepared. SrTiO₃, CaTiO₃ and BaTiO₃ powders synthesized by solid-state reaction method at 1200°C for 2 h were used to prepare the solar cells. Phase-pure SrTiO₃ and BaTiO₃ cells showed higher V_OC than that from TiO₂, but showed lower J_SC and efficiency. To utilize the positive effect to increase the V_OC, P25 TiO₂/SrTiO₃ and P25 TiO₂/BaTiO₃ composite DSC were prepared. For each series, ~30 wt % addition was favorable to increase the photo-electric conversion efficiency.

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In this study, suppression of thermal degradation for polyamide 6 (PA6) resin matrix in carbon fiber reinforced thermoplastic (CFRTP) using hexagonal boron nitride (h-BN) was examined. The CFRTP which was composed of h-BN powder, discontinuous carbon fiber (CF) and PA6 had superior thermal degradation resistance of interface between CF and PA6 resin matrix, compared to the conventional one composed of CF and PA6. Thermal degradation test of CFRTP was carried out by microwave irradiation. In case of the conventional CFRTP irradiated with microwave for 15 s, the thermal degradation was progressed at interface between CFs and PA6 resin matrix. On the other hand, in case of the CFRTP with h-BN, the thermal degradation of interface between CF and PA6 resin matrix was not observed after microwave irradiation for 60 s. Moreover, it was indicated that CFRTP with 2 vol.% or more h-BN took longer melting time than conventional one. It was found that the thermal conductive enhancement of resin matrix with h-BN was effective for suppressing the thermal degradation of interface between CF and TP matrix in CFRTP.

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