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1.
《Ceramics International》2019,45(12):14728-14732
This work demonstrates the successful deposition of bioactive glass (BG) 45S5 coatings on various metallic and ceramic substrates at room temperature under low vacuum condition by using aerosol deposition (AD). This room temperature and particle impact consolidation-based deposition method enabled us to deposit well-adhered and dense BG coatings directly on metallic and ceramic substrates. In vitro tests with human osteoblast-like cells on substrates with a 45S5 BG coating demonstrated high cell activity on the surfaces. All tested materials exhibited high in vitro biocompatibility as no inhibition in cell proliferation could be observed. The utilization of AD process for achieving non-crystalline BG coatings is promising for practical bio-medical applications, e.g., bioactive coatings on bioinert metallic and ceramic substrates. 相似文献
2.
Shunjie Deng Chi Jiang Tianwei Liu Yin Hu Jingjing Ding Maobing Shuai 《Journal of the American Ceramic Society》2019,102(3):1362-1372
Al2O3-Y2O3-SiC composite coatings were prepared on depleted uranium by cathode plasma electrolytic deposition in Al(NO3)3, Y(NO3)3, SiC nanoparticles and anhydrous ethyl alcohol mixture. The resulting coating consisted of an inner barrier layer and an outer porous layer. The SiC nanoparticles were incorporated into the composite coating and decreased the coating porosity by filling the pores. The potentiodynamic polarization test and neutral salt spray test revealed that the corrosion resistance of depleted uranium was enhanced by the composite coating. Moreover, with increasing the content of SiC nanoparticles in the coating, the coating corrosion resistance was improved gradually. 相似文献
3.
《Ceramics International》2020,46(6):7774-7782
In order to inhibit the metal catalytic coking and improve oxidation resistance of single TiN coating, the TiN/Al2O3 double layer coatings were designed as a chemically inert coating for methylcyclohexane supercritical pyrolysis. Internal TiN coatings were prepared by atmospheric pressure chemical vapor deposition using TiCl4–H2–N2 system. The external Al2O3 coatings with different thicknesses were prepared on the TiN surface by polymer-assisted deposition, and the coating with the most suitable thickness was further annealed at different temperatures of 600, 700, 800 and 900 °C. The morphology, elemental and phase composition of TiN/Al2O3 coatings were characterized by SEM, EDX and XRD respectively. The chemical state information of the coating elements was based on Ti 2p, Al 2p core level X-ray photoelectron spectroscopy (XPS) spectra. The results indicated that the external Al2O3 coating will partially peel off at 900 °C annealing temperature. The thermogravimetric analysis results indicated that all TiN/Al2O3 coatings show better oxidation resistance than single-layer TiN coating. The anti-coking test with methylcyclohexane supercritical pyrolysis showed that the TiN/Al2O3 coatings can effectively cover the metal catalytic sites and eliminate metal catalytic coking. However, the acid sites of external Al2O3 coating slightly promoted coking, so the anti-coking ratios of TiN/Al2O3 coatings were smaller than that of TiN. Thus, the addition of external Al2O3 coating can greatly improve the oxidation resistance of TiN coatings with little loss of coking resistance. 相似文献
4.
Maria Rita Cicconi Neamul H. Khansur Udo R. Eckstein Ferdinand Werr Kyle G. Webber Dominique de Ligny 《Journal of the American Ceramic Society》2020,103(4):2443-2452
Aerosol deposition (AD) is a dynamic loading process that can be envisioned as a shock wave loading, necessitating the consideration of the elastic/plastic response of solid materials. Due to the dynamic nature of this process, however, experimental determination of the local pressures during the deposition process is difficult. This work addresses this by investigating the compression and subsequent structure modification of a silicate glass after room-temperature AD on a silicate glass substrate with Raman spectroscopy. Clear structural changes in the short- and middle-range order of the silicate glass were observed, both as intertetrahedral angle distribution and as ring statistic. Therefore, the AD induced permanent densification of the glass, equivalent, in a hydrostatic approximation, to a minimal pressure of 10.5 ± 1.5 GPa during the film deposition process. Furthermore, the analysis of the Nd3+ photoluminescence of the 4F3/2 − 4I9/2 transition provided complementary information on the glass network modifications occurring during film formation. More than a pure hydrostatic densification, the AD seems to present a very intense shear deformation. This work opens up the perspective of evaluating the mechanical response of film-substrate and of the particles themselves, and provides critical information on the mechanisms responsible for the AD film formation. 相似文献
5.
Hiroaki Ashizawa Kiyohara Masakatsu Katsumi Yoshida 《Journal of the American Ceramic Society》2020,103(12):7031-7040
Particle contamination arising from inner ceramic components of the plasma etching equipment has become a serious issue. Yttria (Y2O3) coatings prepared via aerosol deposition (AD) have demonstrated superior plasma resistance in the reduction of particle contamination. The superior particle contamination performance of Y2O3 coatings prepared by AD has been speculatively attributed to its unique microstructure; however, the relationship between the coatings’ microstructure and plasma corrosion behavior has been insufficiently clarified. Herein, we investigated the relationship between the microstructure and plasma corrosion behavior of Y2O3 coatings prepared by the AD method and compared the results with those for coatings prepared by other coating methods. When internal pores are present, these internal pores were selectively plasma corroded; plasma corrosion marks reflecting their pore shape were formed, and the surface roughness increased with increasing plasma exposure time. However, when no internal pores were present, as in the case of the AD coating, the surfaces were homogeneously corroded and maintained their initial surface. As the risk of particle contamination caused by the corrosion of the plasma-resistant coatings is greatly increased with surface roughness, we concluded that the Y2O3 coating prepared via AD will contribute greatly to reducing particle contamination. 相似文献
6.
Dual layer SiC coating on matrix graphite sphere prepared by pack cementation and fluidized‐bed chemical vapor deposition
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Ping Zhou Zujie Zheng Rongzheng Liu Xiaoxue Liu Malin Liu Taowei Wang Ziqiang Li Youlin Shao Hongsheng Zhao Bing Liu 《Journal of the American Ceramic Society》2017,100(8):3415-3424
A dual layer silicon carbide (SiC) coating including inner porous SiC (p‐SiC) layer and outer dense SiC (d‐SiC) layer was fabricated on the matrix graphite (MG) spheres of high‐temperature gas‐cooled reactor fuel elements by pack cementation and fluidized‐bed chemical vapor deposition process to improve the oxidation‐resistant property. Microstructure of the coating demonstrates different density and structure of the two SiC layers with no obvious boundaries between them. Weight gain curves of oxidation tests at 1773 K for 200 hours show that the coating could effectively protected the MG sphere by isolating the air infiltration with p‐SiC layer as the main functional layer and d‐SiC layer as the transition layer to improve the bond strength. Due to the transition function of p‐SiC layer, the coated spheres could understand more than 50 times thermal shocking tests from 1773 K to room temperature with no stress cracking. 相似文献
7.
Mehdi Razavi Mohammadhossein Fathi Omid Savabi Seyed Mohammad Razavi Batoul Hashemi Beni Daryoosh Vashaee Lobat Tayebi 《Ceramics International》2014
In order to improve the corrosion resistance and the surface bioactivity of biodegradable magnesium alloys, a nanostructured akermanite (Ca2MgSi2O7) coating was grown on AZ91 magnesium alloy through electrophoretic deposition (EPD) assisted with micro arc oxidation (MAO) method. The crystalline structures, morphologies and compositions of samples were characterized by X–ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. The in vitro bio–corrosion (biodegradability) and bioactivity behaviors of samples were investigated by electrochemical and immersion tests. The experimental results indicated that the nanostructured akermanite coating could slow down the corrosion rate and improve the in vitro bioactivity of biodegradable magnesium alloy. Thus, magnesium alloy coated with nanostructured akermanite may be a promising candidate to be used as biodegradable bone implants. 相似文献
8.
采用MgO碳热还原和扩散氧化法在镁钙砂表面沉积MgO涂层,研究了MgO涂层的沉积动力学、微观形貌、生长机制以及涂层厚度对镁钙砂抗水化性能的影响。结果表明:随着反应温度的升高,沉积过程存在两个控制机理,在1400~1500℃之间,为化学动力学控制,反应为一级反应,活化能为97.82 kJ·mol-1;在1500~1600℃之间,沉积过程为扩散控制,扩散活化能为19.18 kJ·mol-1;MgO涂层以方镁石和方钙石为基底均呈二维台阶状生长,但二者生长机制并不完全相同;抗水化实验结果显示最佳处理温度为1600℃、沉积时间为6 h,镁钙砂水化质量增加率为0.02%,约是处理前的1/150。 相似文献
9.
《Ceramics International》2023,49(8):11837-11845
Environmental barrier coatings (EBCs) have been expected to be applied on the surface of ceramic matrix composites (CMCs). However, the oxidation and propagation cracking of the silicon bond layer are the most direct causes to induce the failure of EBCs under high temperature service environment. The modification of silicon bond layer has become an important method to prolong the service life of EBCs. In this work, the Yb2O3 have been introduced to the silicon bond layer, and three kinds of tri-layer Yb2SiO5/Yb2Si2O7/(Si-xYb2O3) EBCs with modified Si bond layer by different contents of Yb2O3 (x = 0, 10 vol%, 15 vol%) were prepared by vacuum plasma spray technique. The thermal shock performance and long-term oxidation resistance of the EBCs at 1350 °C were investigated. The results showed that the addition of appropriate amount of Yb2O3 (10 vol%) can improve the structural stability and reduce the cracks of the mixed thermal growth oxide (mTGO) layer by forming the oxidation product of Yb2Si2O7 during long-term oxidation. The excessive addition of Yb2O3 increased the stress during thermal shock as well as accelerated the oxygen diffusion during long-term oxidation, leading to the failure of EBCs. Moreover, the distribution uniformity of Yb2O3 deserves further consideration and improvement. 相似文献
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The purpose of this paper is to demonstrate the use of lunar regolith and the dry aerosol deposition (DAD) method to produce ceramic coatings on polyimide polymer, and to test their mechanical integrity. Ceramic films were produced on Kapton substrates using a custom-built DAD system and lunar mare simulant (LMS) feedstock. Ultrafine grains and impact densification were confirmed using atomic force and electron microscopy. Mechanical properties of the DAD–LMS Kapton samples were evaluated with indentation, tensile, and mandrel bend tests. DAD–LMS coatings tripled the hardness and doubled the indentation modulus of the Kapton surface. Coatings 3–16 µm thick did not have a predictable effect on the ultimate tensile strength or elongation to failure; however, the apparent modulus of elasticity did increase. The coatings were able to withstand significant bending before damage, with critical bend radii of 5 and 1.5 mm for 7.5 µm and 120 nm thicknesses, respectively. Modest heat treatment was shown to reduce the bending strain of coated substrates. Advanced ceramic coatings are of interest for the protection of space and satellite polymers from micrometeoroid impacts, radiation, and atomic oxygen. Lunar posts and habitats will require the development of space manufacturing techniques and in situ resource utilization. 相似文献
13.
This study successfully manufactured a thick, pure SiC coating layer with a thickness of 83.3 μm using vacuum kinetic spray process and investigated the unique impact-induced deposition behavior at room temperature. The simulated result of SiC particle collides with the metallic matrix, or predeposited SiC layer confirmed that particle shock pressure could increase up to the maximum pressure of 27.2 GPa. Moreover, the particles were predicted to fracture to submicrometer size after plastic deformation and those characteristics also matched microstructural observations made with a transmission electron microscope. The SiC coating layer formed an unexpected microstructure composed of bent lattices, fractured submicrometer-sized particles, and amorphous layers. Correlating the microstructure and simulation results suggested that a pure SiC coating layer could be formed using mechanical anchoring and amorphous bonding at room temperature. 相似文献
14.
Yukitoshi Takeshita Takuya Kamisho Seizo Sakata Takashi Sawada Yoshikazu Watanuki Ryuichi Nishio Toshinobu Ueda 《应用聚合物科学杂志》2013,128(3):1732-1739
Micro FTIR analysis was performed to the point with a 50–80 μm spatial resolution to verify the exact structure of a new blend thermoplastic powder coating film. Resistance to certain artificially accelerated conditions and actual outdoor exposure were examined to confirm the performance of the film as a protective coating for use in the telecommunication field. The new blend powder coating film consists of primary polyethylene terephthalate (PET) and secondary polyvinyl butyral (PVB) resins, and has a distinct dual phase structure. Specifically, it forms a continuous PVB phase in a surface layer with a thickness of approximately 100–150 μm. Good corrosion resistance was confirmed in artificially accelerated testing using salt water spray, heat cycle, and accelerated UV tests. Actual outdoor exposure in a metropolitan area (Shinkiba in Tokyo) and a coastal area (Miyake Island) revealed good weathering performance throughout the study period. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
15.
《Journal of the European Ceramic Society》2022,42(5):2097-2106
ZrB2-SiC-Al2O3 (ZSA) and ZrB2-SiC-Si (ZSS) coatings were prepared on the surface of C/C composites by atmospheric plasma spraying. During oxidation at 1200 ℃ for 10 h, the formation of B2O3 in the ZSA coating volatilizes gradually, no glass phase is able to seal cracks and holes, resulting in poor oxidation resistance. On the other hand, the ZSS coating produces a large amount of borosilicate glass phase and still gains 0.8% weight after 10 h. During oxidation at 1500 ℃, a low viscosity SiO2 glass phase forms on the ZSA coating, due to the presence of Al2O3 and this glassy phase has a good ability to seal defects. However, the rapid volatilization of B2O3 in the ZSS coating leads to the formation of large holes in the coating, and to progressively increased viscosity of SiO2 glass phase, resulting in decreased oxidation resistance. 相似文献
16.
Valerie L. Wiesner Bryan J. Harder Narottam P. Bansal 《Ceramics International》2018,44(18):22738-22743
A calcium-magnesium aluminosilicate (CMAS) glass was prepared by melting a sample of desert sand to evaluate the high-temperature interactions between molten CMAS and yttrium disilicate (Y2Si2O7), an environmental barrier coating (EBC) candidate material. Cold-pressed pellets of 80?wt% Y2Si2O7 powder and 20?wt% CMAS glass powder were heat treated at 1200?°C, 1300?°C, 1400?°C and 1500?°C for 20?h in air. The resulting phases were evaluated using powder X-ray diffraction. In the second set of experiments, free standing hot-pressed Y2Si2O7 substrates with cylindrical wells were filled with CMAS powder to a loading of ~35?mg/cm2 and heat treated in air at 1200?°C, 1300?°C, 1400?°C and 1500?°C for 20?h. Scanning electron microscopy, energy-dispersive spectroscopy and electron microprobe analysis were used to evaluate the microstructure and phase compositions of specimens after heat treatment. An oxyapatite silicate (Ca2Y8(SiO4)6O2) phase was identified in all specimens after CMAS exposure regardless of heat treatment temperature. Apatite appeared to form by dissolution of Y2Si2O7 into molten CMAS, reacting with CaO in the melt according to the reaction 4Y2Si2O7 +?2CaO → Ca2Y8(SiO4)6O2 +?2SiO2, and followed by precipitation of the apatite phase. 相似文献
17.
《Ceramics International》2020,46(15):23686-23694
High-quality alumina (Al2O3) coating has an extensive demand in the fields of optoelectronics, solar cells, and corrosion/impurity resistant coatings and cutting tools. The quality of alumina coating depends on its hardness and transparency. To obtain hard and highly transparent alumina coating, which is also a widely used ceramic material, a novel, aerosol deposition approach is presented in which the starting powder, used to fabricate Al2O3 ceramic coatings, is composed of angular and spherical Al2O3 particles. Films fabricated using angular:spherical Al2O3 particle mixtures with ratios of 10:0, 7:3, 5:5, 3:7, and 0:10, showed significant variation in surface roughness and microstructure. The dramatic morphology modulation of the 3:7 angular:spherical Al2O3 mixture film, resulting from the superposition hammering effect caused by the aerosol mixture, improved transmittance (84.7%) and hardness (13.6 GPa). Previous studies used high-energy approaches to optimize Al2O3 film properties. This dual-particle approach, however, produces Al2O3 film with excellent transmittance and hardness while achieving a fast coating speed (32 mm2 × μm/min) without additional thermal treatment. Our proposed approach provides a novel and energy efficient method to produce transparent Al2O3 films with superior durability. 相似文献
18.
Ali Aliabadi Seyed Mohammad Mehdi Hadavi Mohamad Javad Eshraghi 《Ceramics International》2021,47(14):20051-20063
In this study, a hybrid coating comprised of NiCoCrAlY fabricated by HVOF method, Ni–CeO2 composite coated by electrodeposition, and aluminide coating applied by low pressure chemical vapor deposition (LPCVD) method are investigated. To elucidate the formation process of aluminide coating, the microstructure and properties of the applied coatings were examined by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and EDS analyses. It was concluded that the desired β-NiAl phases are uniformly created within a single step on the surface. Furthermore, with the extending of the coating duration from 2 to 4 h, the thickness of the aluminide coating was increased from 14 to 25 μm. The thickness values were increased even further in the presence of Ni–CeO2 coating, where the growth mechanism was also changed. Within 4 h, a coating with a thickness of roughly 50 μm was obtained. Moreover, in the presence of Ni–CeO2 coating, it was observed that the inward diffusion of aluminum was predominant at the beginning of the process, whereas with longer processing durations, the outward diffusion of the nickel becomes dominant instead. 相似文献
19.
《Journal of the European Ceramic Society》2023,43(5):2033-2038
High-energy-density and safe rechargeable batteries are key components to realizing a low-carbon society. All-solid-state Li-metal batteries have the potential to achieve both high safety and high energy densities. However, the large interfacial resistance between solid electrolytes and cathodes is the major challenge for developing all-solid-state Li-metal batteries. Here we deposited a Li-rich layered metal oxide Li1.2Mn0.54Ni0.13Co0.13O2 (LMNC) thin film (6 µm thick) on an Al-doped Li7La3Zr2O12 (LLZO) substrate at room temperature by aerosol deposition. The LMNC particles were coated with Li3BO3 (LBO), which acted as a binder to hold LMNC and LLZO together at heating. As a result, good interfacial contact was achieved between LMNC and LLZO. Yet reactions between LMNC and LBO would occur at heat treatment temperatures above 600 °C. The highest discharge capacity of the all-solid-state Li/LLZO/LBO-LMNC cell at 0.1 C and 60 °C was 223 mAh g-1. The main reason for the cell capacity decay was the cracking of the LBO-LMNC cathode layer during cycling. Searching for a more suitable binder material with a high fracture toughness is crucial for further developing the aerosol-deposited LLZO-based all-solid-state Li metal batteries. 相似文献
20.
Nayereh Asgari Masoud Rajabi 《International Journal of Applied Ceramic Technology》2021,18(1):147-153
The addition of bio-inert ceramics such as alumina and zirconia can significantly improve the mechanical properties of hydroxyapatite bioactive coatings and increase their biocompatibility. In the present study, the surface of a titanium substrate was coated by the electrophoretic deposition method (EPD). Moreover, the reaction bonding process has been used to precipitate the nanocomposite containing the hydroxyapatite (HA), alumina, yitteria-stabilized zirconia (YSZ). The coating process was performed by an electrical power supply and a suspension of hydroxyapatite, aluminum, and YSZ nanopowders. For preparing a suspension consisting of 50% isopropanol and 50% acetone, 0.6 g/L of iodine was used as a stabilizer. Green and sintered coatings were analyzed by FE-SEM and XRD. In addition, the mechanical properties such as bonding strength, hardness, and toughness were measured. The hardness, bonding strength, and toughness of the HA coating were 107 ± 10.3 HV, 10.8 ± 3.2MPa, and 0.72MPa√m, respectively, while those of the HA-Al2O3-YSZ nanocomposite coating were 213 ± 1.8 HV, 35 ± 1.6MPa, and 1.6MPa√m, respectively. 相似文献