共查询到20条相似文献,搜索用时 187 毫秒
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Sol-gel法制备耐蚀涂层的技术及应用 总被引:2,自引:0,他引:2
Sol-gel法制备耐蚀涂层对提高基材的化学耐久性、防止氧化、控制腐蚀有显著的效果,有望完全替代传统材料表面腐蚀控制处理使用的毒性物质铬酸盐处理工艺,可以减轻对环境的污染,是一项可持续发展的表面处理技术.为了阐述该项技术的工艺方法及特点,综述了Sol-gel法制备技术在不同的金属基体--不锈钢、铝合金和铜合金表面中的应用现状和最新研究进展.分析了采用Sol-gel法制备耐蚀涂层可以有效地阻止腐蚀介质对基体金属材料的破坏,延长材料在实际应用环境中的使用寿命等方面的作用原理,从理论上对Sol-gel耐蚀涂层的形成机制和耐蚀机理进行了初步讨论,并对Sol-gel技术的应用前景作一简要展望. 相似文献
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用溶胶-凝胶法制备保护涂层的研究进展 总被引:1,自引:0,他引:1
溶胶-凝胶(Sol-gel)法用于金属及合金表面制备保护涂层可明显提高材料在各种环境下的耐蚀性、抗高温氧化性、耐磨性等性能,从而扩大金属及其合金的应用范围.介绍了Sol-gel涂层的制备技术、涂覆工艺以及涂层热处理的一般原理及特点,总结了该技术制备保护涂层的应用现状及最新研究进展,讨论了制备单组分氧化物涂层如ZrO2涂层、SiO2涂层、CeO2涂层、Al2O3涂层、TiO2涂层,双组分氧化物涂层如ZrO2-CeO2涂层、SiO2-ZrO2涂层以及多组分氧化物涂层的制备方法及涂层对基体材料的保护作用,并对其保护机理进行了初步探讨. 相似文献
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溶胶-凝胶技术制备光化学杂化材料 总被引:3,自引:0,他引:3
溶胶 -凝胶技术是制备有机 -无机杂化材料的重要手段 ,在光致变色、光纤传感和发光等光化学杂化材料制备方面应用前景广阔。提高光致变色染料的稳定性、制备溶胶 -凝胶光纤及降低杂化材料羟基含量是目前的研究重点。 相似文献
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钛基体上氧化铝膜层的耐高温和耐腐蚀性能研究 总被引:3,自引:0,他引:3
钛材高温氧化严重,为了提高其使用性能,采用溶胶-凝胶法在钛合金材料表面制备了耐腐蚀性能优良的三氧化二铝膜层.通过700 ℃下氧化增重的测量、扫描电镜对涂层高温氧化前后表面形貌的观察以及其在3.5%NaCl溶液中的阳极极化曲线测量表明,带涂层的试样在700 ℃、20 h的增重仅有0.028 0 mg/cm2,无涂层的试样增重为1.005 2 mg/cm2;带涂层的试样ΔE=1 203.5 mV,裸露钛合金试样的ΔE=154.6 mV.在钛合金材料表面制备的氧化铝溶胶-凝胶膜层具有提高钛合金材料表面抗高温氧化和耐腐蚀性能的特点. 相似文献
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在高体积分数SiCp/Al复合材料表面镀覆一层Ni-P合金可有效改善其可焊性.为在体积分数60%的SiCp/Al复合材料表面电镀一层Ni-P合金,采用正交试验对电镀工艺参数进行了优化,研究了电镀前预处理工艺,并考察了预处理对电镀层的影响.由正交试验获得了最佳硬度和最佳表面质量的工艺参数;采用SEM、EDS、X射线衍射仪和显微硬度计等对镀层进行表征.研究结果表明:P含量通过影响Ni-P的晶体结构,进而影响其性能,随着P含量(9.38%~15.4%)的增加,Ni-P的非晶态结构越明显,硬度在P含量11.4%时达到最大值723.3 HV;与SiCp/Al表面SiC相上的沉积相比,电沉积Ni-P在Al相上的初始沉积迅速,且长大速度快,导致镀层微观表面凹凸不平.经165℃活化热处理及化学镀18 min后,再电镀40 min,获得的镀层微观表面平整、厚12.90~14.79μm.说明经过优化工艺参数和预处理,可制备表面平整且结合良好的Ni-P电镀层. 相似文献
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Hard coatings are frequently used to give plastics high scratch resistance. Coating hardness and adhesion to the substrate are considered to be key factors influencing scratch resistance, but it is difficult to produce coatings that have both properties. Hybridization of polymers and inorganic materials is a promising approach for solving this problem. We prepared polymer-silica hybrid coatings by using in situ polymerization to carry out radical polymerization of vinyl monomers in a sol-gel solution of alkoxysilanes, and measured the abrasion resistance of the coatings. However, the expected properties were not obtained because the sol-gel reaction did not perfectly proceed on the surface of the coatings under the N2 conditions. We found that curing the hybrid coatings by UV irradiation in air promoted the sol-gel reaction on the surface, resulting in coatings having excellent abrasion resistance. 相似文献
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采用溶胶-凝胶法以Na2SiO3为包覆剂成功地制备了分散性优良负离子粉体,通过不同的添加量,研制能够产生最大负离子浓度的功能涂料。进行了负离子涂料的抗菌性研究,实验结果表明负离子材料具有抗菌性,抗菌效果与涂料的负离子产生量、负离子材料粒径、涂料的距离密切相关,并从微观上对负离子杀菌进行了分析,验证了负离子的生物学效应。 相似文献
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A novel sol-gel method is described for the preparation of solid-phase microextraction (SPME) fibers. The protective polyimide coating was removed from a 1-cm end segment of a 200 μm o.d. fused-silica fiber, and the exposed outer surface was coated with a bonded sol-gel layer of poly(dimethylsiloxane) (PDMS). The chemistry behind this coating technique is presented. Efficient SPME-GC analyses of polycyclic aromatic hydrocarbons, alkanes, aniline derivatives, alcohols, and phenolic compounds in dilute aqueous solutions were achieved using sol-gel-coated PDMS fibers. The extracted analytes were transferred to a GC injector using an in-house-designed SPME syringe that also allowed for easy change of SPME fibers. Electron microscopy experiments suggested a porous structure for the sol-gel coating with a thickness of ~10 μm. The coating porosity provided higher surface area and allowed for the use of thinner coatings (compared with 100-μm-thick coatings for conventional SPME fibers) to achieve acceptable stationary-phase loadings and sample capacities. Enhanced surface area of sol-gel coatings, in turn, provided efficient analyte extraction rates from solution. Experimental results on thermal stability of sol-gel PDMS fibers were compared with those for commercial 100-μm PDMS fibers. Our findings suggest that sol-gel PDMS fibers possess significantly higher thermal stability (>320 °C) than conventionally coated PDMS fibers that often start bleeding at 200 °C. This is due, in part, to the strong chemical bonding between the sol-gel-generated organic-inorganic composite coating and the silica surface. Enhanced thermal stability allowed the use of higher injection port temperatures for efficient desorption of less-volatile analytes and should translate into extended range of analytes that can be handled by SPME-GC techniques. Experimental evidence is provided that supports the operational advantages of sol-gel coatings in SPME-GC analysis. 相似文献
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采用溶胶-凝胶法合成了不同粒径的Al2O3-30%(质量分数)TiO2纳米复合粉体,用喷雾干燥法对合成粉体进行喷雾造粒,造粒后的粉体通过等离子喷涂制备Al2O3/TiO2复合涂层,最后对涂层结构和性能进行了表征。涂层结构和形貌分析表明制备的涂层具有微米/纳米复合结构,初始粉体粒径对涂层的结构和致密度影响很小;涂层摩擦学性能测试表明复合涂层的磨损率随初始粉体粒径的增大而减小,初始粉体粒径为100nm左右时,复合涂层的磨损率最低。复合涂层的磨损机制为裂纹扩展导致的磨损剥落。 相似文献
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This study first prepared B-doped SiO2 coating by hybrid sol-gel method. SiO2 coatings had been successfully used for thermal protection, but its toughness, oxidation resistance and cost are weak points. Hybrid sol-gel method could prepare ultra thin and low cost SiO2 coatings on nickel alloys. And doping B could improve the coatings’ toughness and oxidation resistance. Thermogravimetry, differential thermal analysis and Fourier transform infrared spectroscopy were used to investigate the additives’ effect on coatings’ formations at different temperatures. X-ray photoelectron spectroscopy and X-ray diffraction were used to investigate the coatings’ element distribution and phase. The results showed that B-doped SiO2 thermal protective coatings could withstand 1050 °C, and Si-O-B bond was generated to improve the coatings’ toughness. A crystal mullite phase formed on the coatings’ surface at high temperature by thermal diffusion of Al, which significantly improved B-doped SiO2 thermal protective coatings’ oxidation resistance. 相似文献
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结合炼钢转炉用风机因炉气而导致叶片磨蚀较快的实际情况,从改善叶片材料的角度出发,采用溶胶-凝胶法制备Al2O3-SiO2涂层用在金属基体上进行试验。结果表明在含3%(质量分数)Si02磨粒的水介质中,单一三层的SiO2涂层、SiO2-Al2O3-SiO2涂层及混合溶胶制备的复合涂层的耐冲蚀性相近,均比单一三层的Al2O3涂层及A12O3-Sio2-Al2O3涂层好。混合溶胶制备的复合涂层在3%(质量分数)SiO2磨粒的酸性介质中表现出了良好的耐冲蚀性。 相似文献
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溶胶凝胶法在聚合物/无机纳米复合材料中的应用 总被引:9,自引:0,他引:9
本文对溶胶凝胶法在聚合物/无机纳米复合材料中的应用进行了综述.并对溶胶凝胶法在橡胶增强、光学仪器、功能化涂层以及其它领域中的应用进行了具体的讨论.指出溶胶凝胶过程工艺条件的优化以及分散介质范围的扩大将是溶胶凝胶法在聚合物/无机纳米复合材料中应用的发展方向. 相似文献