共查询到20条相似文献,搜索用时 93 毫秒
1.
2.
本文探讨了溶胶-凝胶法制备多晶氧化铝过程中影响胶体性能的因素,成纤方法与工艺参数,热处理工艺制度及晶相转化关系等一系列问题.实验得到了以莫来石为主晶相长期使用温度超过1500℃的多晶氧化铝纤维. 相似文献
3.
4.
5.
6.
溶胶凝胶法氧化铝分离膜制备工艺探讨 总被引:1,自引:0,他引:1
以异丙醇铝为主要原料,将原料子处理后,用溶胶-凝胶法制备Al2O3,膜,考察胶溶剂的种类和用量、水解温度、回流时间等制备条件对Al2O3,膜微观结构的影响。研究结果表明,选择用HCl作为胶溶剂,调节溶液pH值为2.O-3.5、水与乙醇体积量比为1:1、水解温度为80~85℃左右。通过预处理,合成时间缩短,为6~8h左右,可以制得微观结构性能比较好的Al2O3膜。 相似文献
7.
氧化硅-氧化铝(SiO2-Al2O3)体系凝胶不仅应用广泛,而且其制备及反应机理还可借鉴到碱激发胶凝材料等领域。通过对溶胶-凝胶法合成氧化硅-氧化铝体系凝胶的制备过程及影响因素和影响规律、凝胶的性质和结构表征及合成机理研究进展进行综述,提出目前仍缺乏有关碱(土)金属离子对凝胶结构性能的影响研究以及硅铝含量变化的定量描述数据,建议拓宽研究范畴,结合核磁共振等检测方法,得出该体系结构性能变化准确数据,为氧化硅-氧化铝体系凝胶的设计和应用夯实基础。 相似文献
8.
溶胶-凝胶法制备氧化铝纤维的研究 总被引:2,自引:2,他引:0
采用溶胶-凝胶法,以AlCl3·6H2O、金属Al粉、ZrOCl2·6H2O、和H2O为原料制备氧化铝纤维.主要研究了拉丝助剂(HCl和HAc)、烧结温度及ZrO2添加量对氧化铝纤维性能的影响.研究结果表明同种拉丝助剂添加量越大,可拉丝时间越长.在1000~1400 ℃烧结范围内,烧结温度对纤维的表面结构影响不大;1400 ℃下可以得到晶粒发育完善,晶型完整以及拉伸强度最佳的氧化铝纤维.ZrO2可对氧化铝纤维起到增强作用,但随着ZrO2量的增加,拉伸强度的增加作用逐渐减小. 相似文献
9.
10.
用溶胶-凝胶法制备Al_2O_3涂层工程陶瓷的表面改性研究 总被引:2,自引:1,他引:1
分析了溶胶 -凝胶法制备Al2 O3 溶胶的适宜工艺条件 ,在氧化铝基陶瓷基体上成功地制备了Al2 O3 涂层 ;利用X射线衍射分析和差热分析 (DTA)方法对Al2 O3 凝胶粉末的相变过程进行了研究 .通过分析精磨、热处理、Al2 O3 一次和二次溶胶涂层 4种试样的抗弯强度测量值对材料总体性能进行了估计 .结果表明 :Al2 O3 涂层工程陶瓷可以提高基体的抗弯强度而降低其分散性 ,效果好于单纯的热处理 .通过观察4种试样的表面SEM形貌和两种涂层试样的断面SEM形貌提出了溶胶涂层钝化或弥合表面微裂纹的理论模型 相似文献
11.
Seong Woo Kim 《Korean Journal of Chemical Engineering》2011,28(1):298-303
Using sol-gel method, UV-curable urethane acrylate resin system was hybridized with inorganic silicate network to produce hybrid coating materials with high anti-abrasive property. In preparation of acrylate/SiO2 hybrid materials, various acrylic reactants with multi-functional groups in addition to urethane acrylate oligomer as the main network former were employed to obtain more densified organic network structure with a high degree of cross-linking. As a silane coupling agent, 3-methacryloxypropyl-trimethoxysilane (MPTMS) was used to promote interfacial attraction between UV-cured organic acrylate resin and inorganic silicate component in the hybrid. The addition of MPTMS offered significant effect on the improvement of phase compatibility between organic and inorganic phases, which resulted in stable and homogeneous morphology with a dispersion of nano-sized fine silica particles. The results of morphological observation, glass transition behavior, and optical transparency for the hybrid gels provided an evidence for the increased interfacial attraction between two phases. From the Taber abrasion test for the hybrid coating films, it was revealed that there existed optimal ranges of inorganic silicate precursor TEOS and silane coupling agent MPTMS contents for the preparation of UV cured acrylate/SiO2 hybrid with high abrasion resistant property. 相似文献
12.
13.
Aluminum hydroxide gels were prepared by ihe sol-gel method. The role of acid in sols was investigated through the analysis
of telling lime and hydrolysis rale. The phase transformation of gels with calcination temperatures was also monitored with
X-Ray diffraction.
The gelling times of the aluminum hydroxide sols decreased with the increase of acid content. Exceptionally, the solution
peplized with 0.07 HCI/alkoxide molar ratio look longer time than other solutions until the gellation. The hydrolysis rate
of aluminum hydroxide was much faster as the acid concentration increased during peptization. In the case of NH4OH as a peptizing agent, there was Ihe lower rate of hydrolysis and thus the more alkoxyl groups were remained in the gel. 相似文献
14.
Mirnmoy Misra Deuk-Kyu Hwang Yoon Cheol Kim Jae-Min Myoung Tae Il Lee 《Ceramics International》2018,44(3):2927-2933
An indium-tin-oxide (ITO) thin film with approximately 50 nm thickness was successfully synthesized on glass substrates by using a fully aqueous sol-gel process. The sol was prepared from indium nitrate hydrate and tin fluoride as a precursor. Thermogravimetric analysis confirmed that the sol converted into crystalline ITO at 286 °C. The optical band gap and transmittance of the thin film were observed to increase with annealing temperature and plasma treatment time. X-ray photoelectron spectroscopy and transmittance studies established that the number of oxygen vacancies in the thin film drastically increased with increasing temperature and plasma treatment. The annealing temperature and argon plasma treatment time appear to be key factors in reducing resistivity and increasing the transmittance of the thin film. A considerable decrease in the resistivity of the ITO thin film was observed after Ar plasma treatment. This eco-friendly sol-gel ITO thin film may find potential applications in n-type ohmic electrodes for ink-jet printable electronics. 相似文献
15.
Alumina fibers were synthesized from two different systems, AlCl3-Al powder-H2O and Al(NO3)3-Al powder-H2O, by the sol-gel method. For the former system, gel fibers were obtained from solutions in a composition range of Al powder/AlCl3 molar ratios of 2 to 5. For the latter system, the spinnable range was narrower compared to the aluminum chloride system. The thermogravimetry analysis (TGA) curve of the aluminum chloride system showed a weight loss up to 700‡C while the TGA curve of the aluminum nitrate system showed no weight loss above 400‡C, which indicates that thermal decomposition of Cl- is more difficult than that of NOgk-/3. 相似文献
16.
17.
采用溶胶-凝胶法,以菱镁矿、盐酸和尿素为原料,加入成胶剂柠檬酸并烘干,生成前驱体后利用程序升温在高温下煅烧得到氧化镁晶须。结果表明,制备氧化镁晶须的最佳条件为:反应体系温度100℃,溶液pH值为6,并分别加入MXC-2及DXC-3晶形控制剂。晶须长径比为2030∶1,长度为30μm,并具有良好的结晶状态。 相似文献
18.
O. A. Shilova 《Glass Physics and Chemistry》2005,31(2):201-218
This paper reports on the results of investigations into the specific features of the formation of silicate nanosized films from sols based on tetraethoxysilane (hydrolyzed in an acid medium in the presence of inorganic dopants) on the surface of semiconductor materials. The properties of the films thus prepared are analyzed as functions of the synthesis conditions of sols and the conditions of deposition and heat treatment of the films. It is demonstrated that these films can be used in technology for fabricating semiconductor gas sensors based on SnO2.Original Russian Text Copyright © 2005 by Fizika i Khimiya Stekla, Shilova. 相似文献
19.