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石墨烯对光固化Al2O3陶瓷力学性能的影响 认领 引用
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作者 刘耀 余庆轩 +3 位作者 王中原 文蓉江 李澜波 占丽娜 《热加工工艺》 CAS 北大核心 2026年第13期75-82,共8页
针对光固化Al2O3陶瓷在脱脂烧结后易形成孔洞、力学性能差的问题,系统研究了石墨烯添加对陶瓷浆料流变性、沉降性、固化行为及烧结体力学性能的影响。采用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)对Al2O3粉体进行表面改性,并加入不同含... 针对光固化Al2O3陶瓷在脱脂烧结后易形成孔洞、力学性能差的问题,系统研究了石墨烯添加对陶瓷浆料流变性、沉降性、固化行为及烧结体力学性能的影响。采用γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)对Al2O3粉体进行表面改性,并加入不同含量的石墨烯,制备高固相、低粘度的光固化浆料。通过傅里叶红外光谱、旋转流变仪、沉降试验及Beer-Lambert模型分析,优化了浆料配方与光固化工艺参数。结果表明:当KH560含量为2.5wt%、石墨烯含量为0.01wt%时,浆料粘度最低、沉降分层最少;在曝光时间4 s条件下,添加0.01wt%石墨烯的浆料透射深度为382μm,临界曝光能量为44.3 m J/cm2。经1750℃烧结后,陶瓷零件致密度达99.7%,弯曲强度为27.61 MPa,维氏硬度为13.45GPa。石墨烯通过位阻效应及裂纹偏转机制有效促进了烧结致密化并改善了力学性能。本研究为光固化增材制造高致密、高性能氧化铝陶瓷提供了试验依据。 展开更多
关键词 石墨烯 光固化 Al2O3陶瓷 浆料 流变性能
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釉中SiO2和Al2O3含量对青花瓷“晕散”的影响研究 认领 引用
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作者 李小龙 胡其国 +2 位作者 赵田贵 董伟霞 包启富 《中国陶瓷》 CAS CSCD 北大核心 2026年第7期79-88,共10页
青花瓷作为中国传统文化的瑰宝,在制备烧造过程中,因青花色料、釉料配方组成以及制备工艺的影响,易造成青花装饰出现发色不均匀、线条或者块面在不同朝代或者是同一朝代有不同程度的“晕散”。实验采用场发射扫描电镜(FE-SEM)、傅里叶光... 青花瓷作为中国传统文化的瑰宝,在制备烧造过程中,因青花色料、釉料配方组成以及制备工艺的影响,易造成青花装饰出现发色不均匀、线条或者块面在不同朝代或者是同一朝代有不同程度的“晕散”。实验采用场发射扫描电镜(FE-SEM)、傅里叶光谱(FTIR)、电子探针(EPMA)、光学显微镜(OM)等设备分析青花瓷釉中SiO2和Al2O3含量对青花装饰晕散距离、微观结构、釉层网络结构以及釉中Co2+浓度的影响,结合理论计算阐明了青花瓷“晕散”与釉料黏度之间的关系。实验结果表明,随着釉中SiO2和Al2O3含量的增加,釉层网络结构中Si—O—Si键数量增多并且增强,釉层黏度增大;黏流活化能拟合结果表明,黏流活化能增大,原子间作用力越强,Co2+在釉中扩散越困难,青花瓷线条的“晕散”距离从250μm减小到10μm。本研究有助于从物理化学角度理解青花“晕散”机制,为青花装饰工艺的优化提供科学依据。 展开更多
关键词 青花瓷 SiO2 Al 2O3 晕散 黏流活化能
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镁合金表面超音速等离子喷涂Al-Al2O3/5YSZ涂层的组织与耐磨性能研究 认领 引用
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作者 任东亭 李健 +6 位作者 王文权 张东 邵晓宙 尹厚 郝晓华 温毅 康文凯 《热加工工艺》 CAS 北大核心 2026年第9期106-113,共8页
采用超音速等离子喷涂技术,在AZ61镁合金表面制备了不同Al2O3陶瓷含量的Al-Al2O3(AA)涂层以及不同Al2O3/5YSZ陶瓷含量的Al-Al2O3/5YSZ(AAZ)涂层,研究了YSZ的加入以及陶瓷含量对涂层微观组织、孔隙率、显微硬度... 采用超音速等离子喷涂技术,在AZ61镁合金表面制备了不同Al2O3陶瓷含量的Al-Al2O3(AA)涂层以及不同Al2O3/5YSZ陶瓷含量的Al-Al2O3/5YSZ(AAZ)涂层,研究了YSZ的加入以及陶瓷含量对涂层微观组织、孔隙率、显微硬度以及耐磨性能的影响。结果表明,AAZ涂层的截面组织相比AA涂层得到了细化,组织更为均匀,减少了Al2O3相中的孔隙,YSZ以带状和微小球形颗粒弥散分布。涂层的显微硬度随着Al2O3/5YSZ含量的增加而增大,相比AA涂层,AAZ涂层具有更高的硬度值。在滑动摩擦磨损试验中,AAZ涂层硬度的提升使涂层的黏着磨损程度相较AA涂层降低。50%陶瓷含量的AAZ涂层的耐磨性低于30%和70%陶瓷含量的涂层,涂层原始组织中大量的相界面缝隙降低了金属相与陶瓷颗粒的粘结强度,导致陶瓷颗粒的脱落,增加了摩擦系数和磨损速率。30%陶瓷含量的AAZ涂层发生了磨粒磨损和黏着磨损。70%陶瓷含量的AAZ涂层具有最优的耐磨性,磨痕中散落的磨屑在磨损中起到了减摩润滑的作用。 展开更多
关键词 超音速等离子喷涂 镁合金 Al-Al2O3涂层 氧化钇稳定氧化锆(YSZ) 孔隙率 耐磨性
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退火对原子层沉积W/Al2O3纳米薄膜形貌与电学性能的影响 认领 引用
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作者 高管哗 王国政 +1 位作者 蒋恩桐 王天昊 《物理化学进展》 2026年第2期110-121,共12页
在氮气气氛下对原子层沉积法制备的W/Al2O3薄膜进行了退火处理,利用高阻测试仪、扫描电子显微镜及能量色散X射线谱对薄膜进行表征,研究了退火对薄膜电学性能及形貌的影响。结果表明,在1 h退火时间下,400℃~600℃退火不仅使薄膜方块电阻... 在氮气气氛下对原子层沉积法制备的W/Al2O3薄膜进行了退火处理,利用高阻测试仪、扫描电子显微镜及能量色散X射线谱对薄膜进行表征,研究了退火对薄膜电学性能及形貌的影响。结果表明,在1 h退火时间下,400℃~600℃退火不仅使薄膜方块电阻数值明显降低,而且随退火温度升高呈持续下降趋势,当退火温度上升至700℃~800℃时,方块电阻偏离下降趋势,出现了明显上升趋势;当退火时间延长至2 h时,薄膜在400℃~500℃条件下仍保持下降趋势,但在600℃条件下方块电阻出现明显跃升。SEM与EDS结果表明,电学异常与薄膜表面连续性下降密切相关。 展开更多
关键词 原子层沉积 W/Al2O3纳米薄膜 退火 方块电阻 表面形貌
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Tb3+离子掺杂的Al2O3基发光材料的微波水热合成与性能 认领 引用
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作者 程文俊 刘静 张俊计 《纳米技术》 2026年第2期17-25,共9页
以Al(NO3)3·9H2O和尿素为原料,采用微波水热–焙烧法制备了稀土离子Tb3+掺杂的Al2O3基发光材料。利用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)、同步热分析仪(TG-DSC)、荧光光谱仪(FS)和Chromaticity Diagram等对产物的结构、形貌... 以Al(NO3)3·9H2O和尿素为原料,采用微波水热–焙烧法制备了稀土离子Tb3+掺杂的Al2O3基发光材料。利用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)、同步热分析仪(TG-DSC)、荧光光谱仪(FS)和Chromaticity Diagram等对产物的结构、形貌、发光性能和CIE色度进行分析和表征。结果表明,在180℃下微波水热30 min,可制备出结晶良好的叶片状勃姆石。勃姆石经不同温度的焙烧,由γ-Al2O3向δ-Al2O3转变,焙烧后的样品形貌基本保留前驱体的形貌。掺杂Al2O3基发光材料的发光来自Tb3+的5D4→7Fj (j = 3, 4, 5, 6)能级跃迁发射,发光强度随焙烧温度的提高趋于增强,CIE色度随焙烧温度变化不明显,呈绿色。 展开更多
关键词 微波水热法 Al2O3基质 发光性能
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Laser Cladding Al-Si/Al_2O_3-TiO_2 Composite Coatings on AZ31B Magnesium Alloy 认领 引用 被引量:4
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作者 崔泽琴 YANG Hongwei +2 位作者 王文先 WU Hongliang XU Bingshe 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第6期1042-1047,共6页
To improve the wear resistance and corrosion resistance of magnesium alloys, a 5 kW continuous wave CO2 laser was used to investigate the laser surface cladding on AZ31 B magnesium alloys with Al-Si/Al2O3-TiO2 composi... To improve the wear resistance and corrosion resistance of magnesium alloys, a 5 kW continuous wave CO2 laser was used to investigate the laser surface cladding on AZ31 B magnesium alloys with Al-Si/Al2O3-TiO2 composite powders. A detailed microstructure, chemical composition, and phase analysis of the composite coatings were studied by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The laser cladding shows good metallurgical bonding with the substrate. The composite coatings are composed of Mgl7Al12, Al3Mg2, Mg2Si, Al2O3, and TiO2 phases. Compared to the average microhardness (50HV0.05) of the AZ3 1 B substrate, that of the composite coatings (230HV0.05) is improved significantly. The wear resistances of the surface layers were evaluated in detail. The results demonstrate that the wear resistances of the laser surface-modified samples are considerably improved compared to the substrate. It also show that the composite coatings exhibit better corrosion resistance than that of the substrate in 3.5wt% NaCI solution. 展开更多
关键词 AZ31B magnesium alloy laser cladding Al-Si/Al2O3-TiO2 composite coating wear resistance corrosion resistance
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Al2O3coated polyimide porous films enable thin yet strong polymer-in-salt solid-state electrolytes for dendrite-free lithium metal batteries 认领 引用
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作者 Haotian Zhang Shengfa Feng +6 位作者 Mufan Cao Xiong Xiong Liu Pengcheng Yuan Yaping Wang Min Gao Long Pan Zhengming Sun 《Chinese Chemical Letters》 SCIE CAS CSCD 2025年第8期492-497,共6页
The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al2O3-coated polyimide(AO/PI)porous film as ... The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al2O3-coated polyimide(AO/PI)porous film as a high-strength substrate to support fast-ion-conducting polymer-in-salt(PIS)solid-state electrolytes,aiming to suppress lithium dendrite growth and improve full-cell performance.The Al2O3coating layer not only refines the wettability of polyimide porous film to PIS,but also performs as a high modulus protective layer to suppress the growth of lithium dendrites.The resulting PI/AO@PIS exhibits a small thickness of only 35μm with an outstanding tensile strength of 11.3 MPa and Young's modulus of 537.6 MPa.In addition,the PI/AO@PIS delivers a high ionic conductivity of 0.1 m S/cm at 25°C.As a result,the PI/AO@PIS enables symmetric Li cells to achieve exceptional cyclability for over 1000 h at 0.1 m A/cm2without noticeable lithium dendrite formation.Moreover,the PI/AO@PIS-based LiFePO4||Li full cells demonstrate outstanding rate performance(125.7 m Ah/g at 5 C)and impressive cycling stability(96.1%capacity retention at 1 C after 200 cycles).This work highlights the efficacy of enhancing the mechanical properties of polymer matrices and extending cell performance through the incorporation of a dense inorganic interface layer. 展开更多
关键词 Polymer-in-salt solid-state electrolytes Inorganic interface layer Al2O3interfaciAl layer Li dendrites Cycling performance
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纳米Al2O3增强铝基复合材料制备技术及力学性能研究进展 认领 引用 被引量:4
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作者 荣智峥 魏午 +4 位作者 赵宇 毕舰镭 高阳 黄晖 聂祚仁 《材料工程》 EI CAS CSCD 北大核心 2025年第5期130-144,共15页
纳米Al2O3/Al复合材料作为轻质高性能结构材料,可实现轻量化节能减排,在航空航天、汽车工业、船舶制造、国防及5G电子通讯等领域具有广阔的应用前景。本文主要介绍高能球磨粉末冶金法、超声辅助铸造法、搅拌摩擦法、增材制造法、... 纳米Al2O3/Al复合材料作为轻质高性能结构材料,可实现轻量化节能减排,在航空航天、汽车工业、船舶制造、国防及5G电子通讯等领域具有广阔的应用前景。本文主要介绍高能球磨粉末冶金法、超声辅助铸造法、搅拌摩擦法、增材制造法、原位反应法等国内外纳米Al2O3/Al复合材料制备技术。总结分析纳米Al2O3增强体、增强体与铝基体的界面微结构、增强体的尺寸和含量、铝基体的晶粒尺寸、增强体的分散性和微观构型设计对纳米Al2O3/Al复合材料力学性能的影响。概述了纳米Al2O3/Al复合材料中主要的强化机制。最后,展望了纳米Al2O3/Al复合材料未来在高增强体体积分数的大尺寸制备技术、非均质构型优化以及高强耐热结构功能一体化等方面的发展方向。 展开更多
关键词 纳米Al2O3 铝基复合材料 制备方法 力学性能 强化机制
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Preparation of Al2O3 nanowires on 7YSZ thermal barrier coatings against CMAS corrosion 认领 引用 被引量:11
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作者 Xiao-feng ZHANG Shao-peng NIU +5 位作者 Zi-qian DENG Min LIU Hong LI Chun-ming DENG Chang-guang DENG Ke-song ZHOU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第11期2362-2370,共9页
The commonly-employed material for thermal barrier coatings(TBCs)is 7 wt.%Y2O3 ZrO2(7YSZ),generally deposited by electron beam-physical vapor deposition(EB-PVD).Due to the increasing demand for higher operating temper... The commonly-employed material for thermal barrier coatings(TBCs)is 7 wt.%Y2O3 ZrO2(7YSZ),generally deposited by electron beam-physical vapor deposition(EB-PVD).Due to the increasing demand for higher operating temperature in aero-derivative gas turbines,a lot of effort has been made to prevent the premature failure of columnar 7YSZ TBCs,which is induced by the microstructure degradation,sintering and spallation after the deposition of infiltrated siliceous mineral(consisting of calcium magnesium aluminum silicate(CaO MgO Al2O3 SiO2,i.e.,CMAS)).A new method called Al-modification for columnar 7YSZ TBCs against CMAS corrosion was present.The Al film was magnetron-sputtered on the surface of the columnar 7YSZ TBCs,followed by performing vacuum heat treatment of the Al-deposited TBCs.During the heat treatment,the molten Al reacted with ZrO2 to formα-Al2O3 overlay that effectively hindered CMAS infiltration.Moreover,the Al film could evaporate and re-nucleate,leading to the generation of Al2O3 nanowires,which further restrained the moving of molten CMAS. 展开更多
关键词 thermal barrier coating CMAS corrosion Al-modification Al2O3 nanowires
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Effects of Al_2O_3 Nano-additive on Performance of Micro-arc Oxidation Coatings Formed on AZ91D Mg Alloy 认领 引用 被引量:27
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作者 Yan Wang Dongbo Wei +1 位作者 Jie Yu Shichun Di 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2014年第10期984-990,共7页
Ceramic coatings were prepared on AZ91 D Mg alloy by micro-arc oxidation (MAO) in aluminate electrolytes, with Al2O3 nano-additive suspending at different concentrations. Effects of nano-additive concentration on th... Ceramic coatings were prepared on AZ91 D Mg alloy by micro-arc oxidation (MAO) in aluminate electrolytes, with Al2O3 nano-additive suspending at different concentrations. Effects of nano-additive concentration on the structure, phase composition, hardness and anti-corrosion property of the MAO coatings were analyzed by scanning electron microscopy, X-ray diffraction, micro-hardness test and electrochemical method, respectively. The results revealed that Al2O3 nano-particles were mostly incorporated into ceramic coating chemically, transferred into MgAl2O4, rather than being trapped mechanically during MAO process. With the increase of Al2O3 concentration, the voltage-time response, content of MgAl2O4, hardness and anti-corrosion property increased. However, when the concentration varied from 10 g/L to 15 g/L, these behaviors and properties changed only a little. This result indicated that, after the concentration of Al2O3 nano-additive reaching 10 g/L, the incorporation of Al2O3 nano-particles turned into a saturation state, due to the complex process during MAO treatment. Therefore, 10 g/L might be a proper concentration for MAO coating to incorporate Al2O3 nano-particles, 展开更多
关键词 Micro-arc oxidation Al2O3 nano-additive Mg alloy Corrosion Hardness
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Tribological behavior and mechanism of NiCrBSi-Y_2O_3 composite coatings 认领 引用 被引量:8
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作者 蔡滨 谭业发 +2 位作者 谭华 敬奇锋 张中威 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2002-2010,共9页
The NiCrBSi-Y2O3 composite coatings were prepared on the surface of 45 carbon steel by plasma spray, the microstructure and tribological properties of the coatings were investigated. The results show that the NiCrBSi-... The NiCrBSi-Y2O3 composite coatings were prepared on the surface of 45 carbon steel by plasma spray, the microstructure and tribological properties of the coatings were investigated. The results show that the NiCrBSi-Y2O3 composite coatings are mainly composed of γ-Ni, CrB, Cr7C3 and Y2O3. With addition of Y2O3, hard phases such as CrB, Cr7C3 emerge in composite coating, and the density of the composite coatings also increases. The NiCrBSi-0.5Y2O3 composite coating presents excellent tribological properties. Its friction coefficient is 0.175, which is about 37% of that of the pure NiCrBSi coating. The mass wear loss is 1.2 mg, which is reduced by 43% compared with the pure NiCrBSi coating. When the loads are 6-10 N, the NiCrBSi-0.5Y2O3 composite coating suffers from slight wear and the wear mechanisms are mainly adhesive wear accompany with slight micro-cutting wear and micro-fracture wear. As the load increases to 12 N, the wear mechanisms are adhesive wear and severe micro-cutting wear. 展开更多
关键词 plasma spray composite coating NiCrBSi Y2O3 friction wear
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Influence of La2O3 addition on nano indentation hardness and residual stress of Stellite 6 coating prepared by plasma cladding 认领 引用 被引量:12
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作者 Yongchao Fang Xiufang Cui +2 位作者 Zhaobing Cai Chang Wang Guo Jin 《Journal of Rare Earths》 SCIE EI CAS CSCD 2018年第8期873-878,共6页
One of the problems limiting the application of Stellite 6 coating is the residual stress resulting in cracks in the coating easily. In order to reduce the residual stress and increase the nano-indentation hardness,La... One of the problems limiting the application of Stellite 6 coating is the residual stress resulting in cracks in the coating easily. In order to reduce the residual stress and increase the nano-indentation hardness,La2 O3 was added to Stellite 6 coating in this study, and the influence on the microstructure, nano indentation hardness and residual stress of the coatings were investigated by scanning electron microscopy(SEM) with energy dispersive spectrum(EDS), X-ray diffraction(XRD) and nano-indentation tester. Results indicate that the addition of La2 O3 leads to the phenomenon that the dendrite is partly transformed into the equiaxed grain, which results in the grain refinement. The nano-indentation hardness of coatings is improved, which is attributed to the fine-grain strengthening and dispersion strengthening effect of La2 O3. With the addition of La2 O3, the residual stress in coatings is decreased significantly. Especially, when the content of La2 O3 is 0.8 wt%, the nano indentation hardness increases by 1.31 times and residual stress decreases to 20 percent, compared with coating without La2 O3. 展开更多
关键词 Plasma cladding La2O3/Stellite 6 composite coating Microstructure Nano-hardness Residual stress Rare earths
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Effect of MoSi_2 content on dielectric and mechanical properties of MoSi_2/Al_2O_3 composite coatings 认领 引用 被引量:7
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作者 WU Zhi-hong ZHOU Wan-cheng +1 位作者 LUO Fa ZHU Dong-mei 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第1期111-116,共6页
Molybdenum disilicide (MoSi2) sheath and aluminum oxide (Al2O3) core blended powders were fabricated by spray drying. A derived coating material was produced for the application as microwave absorbers using the as... Molybdenum disilicide (MoSi2) sheath and aluminum oxide (Al2O3) core blended powders were fabricated by spray drying. A derived coating material was produced for the application as microwave absorbers using the as prepared powders by atmospheric plasma spray (APS) technology. The effects of MoSi2/Al2O3 mass ratio on the dielectric and physical mechanical properties of the composite coatings were investigated. When the MoSi2 content of the composites increases from 0 to 45%, the flexure strength and fracture toughness improve from 198 to 324 MPa and 3.05 to 4.82 MPa-m1/2 then decline to 310 MPa and 4.67 MPa-m1/2, respectively. The dielectric loss tangent increases with increasing MoSi2 content, and the real part of permittivity decreases conversely over the frequency range of 8.2-12.4 GHz. These effects are due to the agglomeration of early molten MoSi2 particles and the increase of the electrical conductivity with increasing MoSi2 content. 展开更多
关键词 MoSi2/Al2O3 composite coating atmospheric plasma spraying mechanical properties dielectric properties
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Interface characteristics of Al_2O_3-13%TiO_2 ceramic coatings prepared by laser cladding 认领 引用 被引量:4
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作者 高雪松 田宗军 +1 位作者 刘志东 沈理达 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2498-2503,共6页
Al2O3-13%TiO2 (mass fraction) coatings, prepared by laser cladding on nickel-based alloy, were heated using high frequency induction sources. The coating microstructure and the interface between bond coating and cer... Al2O3-13%TiO2 (mass fraction) coatings, prepared by laser cladding on nickel-based alloy, were heated using high frequency induction sources. The coating microstructure and the interface between bond coating and ceramic coating were characterized by SEM, XRD and EDS. The results show that two-layer substructure exists in the ceramic coating: one layer evolving from fully melted region where the sintered grains grow fully; another layer resembling the liquid-phase-sintered structure consisting of three-dimensional net where the melted Al2O3 particles are embedded in the TiO2-rich matrix. The mechanism of the two-layer substructure formation is also explained in terms of the melting and flattening behavior of the powders during laser cladding processing. The spinel compounds NiAl2O4 and acicular compounds Cr2O3 are discovered in the interface between bond coating and ceramic coating. It proves that the chemical reactions in the laser cladding process will significantly enhance the coating adhesion. 展开更多
关键词 ceramic coating nickel alloy laser cladding Al2O3-TiO2 high frequency induction
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Influence of particulate morphology on microstructure and tribological properties of cold sprayed A380/Al2O3 composite coatings 认领 引用 被引量:9
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作者 Xiang Qiu Naeem ul Haq Tariq +5 位作者 Lu Qi Jun-Rong Tang Xin-Yu Cui Hao Du Ji-Qiang Wang Tian-Ying Xiong 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2020年第9期9-18,共10页
In this study,three kinds of A380/Al2O3 composite coatings were prepared by cold spray(CS)using spherical,irregular and spherical+irregular shaped Al2O3 particulates separately mixed in the original A380 alloy powders... In this study,three kinds of A380/Al2O3 composite coatings were prepared by cold spray(CS)using spherical,irregular and spherical+irregular shaped Al2O3 particulates separately mixed in the original A380 alloy powders.The influence of Al2O3 particulates’morphology on the microstructural characteristics(i.e.retention of Al2O3 content in coatings,coating/matrix interfacial bonding,pore size distribution and morphology etc.)and wear performance of the coatings was investigated by scanning electron microscopy(SEM),X-ray computed tomography(XCT)and 3-D optical profilometry.Results indicated that the spherical Al2O3 showsobvious tamping effect during deposition process.As a result,the interfaceshowedawavy shape while the matrix and particulates were mechanical interlocked with much improved adhesion.In addition,the porosity of the coating was minimized and the pores exhibited curved spherical structure with reduced dimensions.The irregular Al2O3 particles predominantly displayed the embedding effect together with fragmentation of Al2O3 particulates.Consequently,poor coating/matrix interfacial bonding,high porosity and the formation of angular-shaped pores were resulted in the coating.Dry sliding wear tests results revealed that the wear resistance of the coating is directly related with the retained content of Al2O3 in the coating.The coating containing irregular Al2O3 particulates displayed superior wear performance with its wear rate one seventh of that of the pure A380 alloy coating.The coating containing both kinds of Al2O3 particulates showed mixed characteristics of above two kinds of Al2O3 composite coatings. 展开更多
关键词 Cold spray Al2O3 particulates X-ray computed tomography Wear test
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Influence of pyrolytic carbon coatings on complex permittivity and microwave absorbing properties of Al_2O_3 fiber woven fabrics 认领 引用 被引量:6
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作者 丁冬海 周万城 +1 位作者 罗发 朱冬梅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期354-359,共6页
The pyrolytic carbon (PyC) coatings were fabricated on A1203 fiber fabrics by the method of chemical vapor deposition (CVD). The microstructures of A1203 fibers with and without PyC coatings were characterized by ... The pyrolytic carbon (PyC) coatings were fabricated on A1203 fiber fabrics by the method of chemical vapor deposition (CVD). The microstructures of A1203 fibers with and without PyC coatings were characterized by SEM and Raman spectroscopy. The influence of deposition time of PyC on the DC conductivity (ad) of A1203 filaments and complex permittivity of fabrics at X band (8.2-12.4 GHz) were investigated. The values of Crd and complex permittivity increase with increasing deposition time of PyC. The electron relaxation polarization and conductance loss were supposed to be contributed to the increase of ε' and ε", respectively. In addition, the reflection loss (RL) of fabrics was calculated. The results show that the microwave absorbing properties of Al2O3 fiber fabrics can be improved by PyC coatings. The best RL results are for 60 min-deposition sample, of which the minimum value is about -40.4 dB at about 9.5 GHz and the absorbing frequency band (AFB) is about 4 GHz. 展开更多
关键词 complex permittivity pyrolytic coating Al2O3 fiber fabric
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Preparation of Al_2O_3/Au nano-laminated composite coatings and their oxidation resistance on stainless steel 认领 引用 被引量:3
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作者 高俊国 陆峰 +2 位作者 汤智慧 王长亮 何业东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2491-2497,共7页
Al2O3/Au nano-laminated composite coatings were prepared by means of magnetron sputtering. The coating was compact and comprised of nano-laminated Al2O3 and Au layers. High temperature cyclic oxidation test was employ... Al2O3/Au nano-laminated composite coatings were prepared by means of magnetron sputtering. The coating was compact and comprised of nano-laminated Al2O3 and Au layers. High temperature cyclic oxidation test was employed to investigate the oxidation resistance of the composite coatings. The results revealed that the applied Al2O3/Au nano-laminated composite coatings improved the oxidation and spallation resistance of the stainless steel substrate significantly. The mechanism accounting for oxidation resistance was related with the suppression of inward oxygen diffusion and selective oxidation of Cr in the substrate. The mechanism accounting for spallation resistance was attributed to the relaxation of thermal stress by the nano-laminated structure. 展开更多
关键词 Al2O3/Au composite coatings magnetron sputtering oxidation resistance spallation resistance
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Effects of Yttrium Ion on Formation Mechanism of ZrO_2-Y_2O_3 Ceramic Coatings Formed by Plasma Electrolytic Oxidation on Al-12Si Alloy 认领 引用 被引量:4
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作者 王萍 LI Jianping +2 位作者 GUO Yongchun YANG Zhong WANG Jianli 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第5期1044-1048,共5页
ZrO2-Y2O3 ceramic coating was produced by plasma electrolytic oxidation (PEO) on ZAlSil2Cu3Ni2 alloy. The microstructure and phase composition of the coating were investigated by SEM and XRD.: The results show that... ZrO2-Y2O3 ceramic coating was produced by plasma electrolytic oxidation (PEO) on ZAlSil2Cu3Ni2 alloy. The microstructure and phase composition of the coating were investigated by SEM and XRD.: The results show that adding an appropriate amount of yttrium ion can improve the growing rate of ceramic coating at different oxidation stages and decrease arc voltage. The thickness of ZrO2-Y2O3 coating is 16 μn thicker than that of ZrO2 coating and the maximum oxidation rate improves by 0.6 μm/min. In addition, the arc voltage decreases from 227 to 172 V. It can be seen that the rate of oxidation firstly increases to some extent and then decreases with the content of yttrium ion increasing. The growth rate reaches the maximum while the content of yttrium ion is 0.05 g-L-1The maximum thickness is 90 μm.Compared to ZrO2 coating, the micropores of ZrO2-Y2O3 coating are less and the ceramic layer is repeatedly deposited by ZrO2 and Y2O3 ceramic particles. Meanwhile, the binding force between coating and substrate is better and the coating is uniform and compact. The ceramic layer is mainly composed of c-Y0.15Zr0.85O1.93□0.07, m-ZrO2, α-Al2O3, ,γ-Al2O3 and Y2O3. It is indicated that ZrO2 has beert fully stabilized by yttrium ion through the formation of solid solution. 展开更多
关键词 Al-12Si alloys yttrium ion plasma electrolytic oxidation ZrO2-Y2O3 ceramic coating
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Fabrication and characterization of Al_2O_3-metal composite coating on steel plate with nonpressure combustion synthesis 认领 引用 被引量:3
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作者 Chang-Hao Wang Ze-Hua Wang +3 位作者 Ze-Hua Zhou Shao-Qun Jiang Xiao-Feng Xue Jing-Jing Yao 《Rare Metals》 SCIE EI CAS CSCD 2013年第4期390-396,共7页
Al2O3-metal composite coatings with different reactants and diluents were fabricated on mild steel plate with nonpressure combustion synthesis process. The coat-ings were characterized by means of X-ray diffraction, s... Al2O3-metal composite coatings with different reactants and diluents were fabricated on mild steel plate with nonpressure combustion synthesis process. The coat-ings were characterized by means of X-ray diffraction, scanning electron microscopy, and energy-dispersive spec-trometry, respectively. Thermal shock tests were carried out to determine the bond strength of the coating with the steel substrate. The results indicate that the coating is composed of α-A1203, α-(Fe-Cr) and Al2SiO5 as the main phases. It is found that the coating with the diluents of Al2O3-SiO2 and transition layer of Al2O3-Cr presents the hi.ghest hardness of 2270 HV0.2 and the lowest porosity of 3.93 %. Owing to a metallurgical bond of the coating-to-substrate, the coating exhibits a good thermal shock resistance. 展开更多
关键词 Combustion synthesis Al2O3-metAlcomposite coating Diluents Thermal shock resistance
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Damage Mechanism of Al_2O_3 Ceramic Coatings Irradiated by CO_2 CW Laser 认领 引用 被引量:3
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作者 李东荣 王富耻 +2 位作者 马壮 王全胜 柳彦博 《Journal of Beijing Institute of Technology》 EI CAS 2008年第2期227-231,共5页
Rules and mechanism of damage in Al2O3 coatings irradiated by CO2 CW laser are studied in order to improve the ability of parts of equipment standing against the high power laser. Al2O3 coatings were sprayed by air pl... Rules and mechanism of damage in Al2O3 coatings irradiated by CO2 CW laser are studied in order to improve the ability of parts of equipment standing against the high power laser. Al2O3 coatings were sprayed by air plasma spray(APS) on the 45^# steel substrate, and then were irradiated by CO2 CW laser from 795 W/cm^2 to 31 830 W/cm^2. As the output power of the laser is increasing, its porosity is increasing and cracks are appearing and spreading quickly, And also the phase will transform from γ-Al2O3 to a-Al2O3 in the damaged areas. When the energy density is 17 507 W/cm^2, the coatings are destroyed completely. The thermal infection field on substrate is rather small. The laser energy is depleted by the phase transformation and cracks in Al2O3 coatings during the laser thermal shock. 展开更多
关键词 CW laser plasma spray Al2O3 coatings demolishment
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