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1.
张谦  何涌 《中国陶瓷》2008,44(5):38-42
粉煤灰堇青石玻璃陶瓷采用处理后的武汉阳逻电厂粉煤灰为主要原料合成.X射线粉晶衍射(XRD)分析样品的主晶相为堇青石,次晶相为尖晶石.图像分析显示堇青石含量达到84.12%.电子背散射图像显示尖晶石和玻璃相均匀弥散分布在堇青石基体中,气孔分布较均匀.粉煤灰堇青石玻璃陶瓷的热膨胀系数α1为2.80×10-6B/℃(1000℃).样品经过在1200℃到室温(空气)的范围分段淬火(温度间隔为200℃)后,材料的弹性模量不但没有下降,反而略有上升,表明材料抗热震能力△T≈1 200℃.  相似文献   

2.
采用循环伏安法在氧化铟锡(ITO)导电玻璃表面上电沉积金纳米颗粒,再用十八硫醇进行二次修饰,得到硫醇修饰的ITO镀金材料.随后对此材料进行扫描电子显微镜(SEM)、X射线衍射(XRD)、接触角测定、紫外扫描等表征.根据XRD结果显示金粒子已成功沉积在ITO玻璃上且分布均匀;考察电沉积圈数(20~200段)对样品接触角的...  相似文献   

3.
采用粉末冶金法经1000℃烧结制备了可加工硅碱钙石微晶玻璃/金属铜功能梯度复合材料(functionally gradient materials,FGM),其中金属含量(质量分数)为0,20%,40%,60%,80%和100%,呈非对称梯度变化.通过金相显微镜、扫描电镜、X射线电子能谱等分析了材料的微观结构和微区元素含量,用万能材料试验机测试了复合材料的弯曲强度.结果表明:硅碱钙石微晶玻璃/金属FGM的结构呈宏观不均匀且微观连续变化,微晶玻璃相与金属粉末相结合紧密,两相均相对独立,两者之间没有发生化学反应;随着金属粉末含量的增加,硅碱钙石微晶玻璃/金属功能梯度复合材料中各梯度层的热膨胀系数和力学性能逐渐变化.  相似文献   

4.
尾矿微晶玻璃的制备及其性能研究   总被引:5,自引:1,他引:4  
研究了以广西北海的高岭土尾矿为主要原料,采用烧结法制备矿渣微晶玻璃的可行性.确定了制备堇青石微晶玻璃的配方(质量分数/%):尾矿53.2,氧化镁18.0,氧化铝16.0,氧化铈4.4,其它8.4.采用X射线衍射(XRD)和扫描电镜(SEM)等手段研究了热处理工艺对微晶玻璃的相组成、微结构和烧结特性以及介电性能的影响.结果说明:烧结样品可以在900℃完全致密化,此时样品的主晶相为α-堇青石.该材料具有低的介电常数和低的线胀系数,是一种有应用前景的低温共烧陶瓷基板材料.  相似文献   

5.
研究了MgO-Al2O3-SiO2系统微晶玻璃中ZnO含量对微晶玻璃结构及透光性能的影响.采用差热分析、X射线衍射、场发射扫描电镜、紫外-可见-近红外分光光度计对材料进行测试.结果表明:透明微晶玻璃主晶相为尖晶石晶体:ZnO含量的增加使玻璃析晶程度提高,析出晶体尺寸变小且分布更加均匀;添加2%(质量分数,下同)的ZnO...  相似文献   

6.
应用扫描电子显微镜、X射线衍射及示差扫描量热法等技术研究了一种SiO2-Al2O3-CaO-MgO-Fe2O3-ZrO-F玻璃陶瓷析晶特征和组织形貌.结果表明:玻璃转变温度为725 ℃左右,在730 ℃后形成了分布均匀的孔状非晶态分相现象.在第一放热峰温度(820 ℃)析晶时,玻璃样品为表面析晶,析出晶体为钙长石(CaAl2Si2O8)和硅灰石(CaSiO3).从表面向内部分别形成枝状晶体、枝状晶体和粒状晶体、粒状晶体三层不同的表面析晶形态.在1040 ℃保温后,玻璃样品中表面析晶和整体析晶共存,析出晶相均以钙长石为主.  相似文献   

7.
聚光腔是固体激光器中关键的光学元件,用于聚光腔的材料应具备高的反射率,同时其反射特性必须与激光工作物质吸收带相适应这一基本要求,聚光腔所选用的材料主要有金属(把金、银、铝镀制在金属基体上)、高分子(聚四氟乙烯)、玻璃(把陶瓷粉末包裹在玻璃管中)和漫反射陶瓷。漫反射陶瓷材料对激光工作物质的辐照光场均匀,  相似文献   

8.
用杉木木粉浸渍高分子先驱体有机硅树脂,改变烧结温度和保温时间制备 SiOC 多孔木质陶瓷。用 X 射线衍射、扫描电子显微镜、红外光谱及热分析对样品的物相及微观结构进行了表征,并用四探针法测试样品的电学性能。结果表明:样品由 SiOC 玻璃相、α-石英和自由碳组成,化学结构主要含有 Si—O,Si—O—R,Si—C,C=C 和 C—H2。α-石英颗粒呈球状分布在样品的孔洞表面。样品在 Ar 中具有较好的热稳定性。但由于 SiOC 玻璃相和自由碳的氧化反应,样品在 O2中的质量损失较大。当烧结温度达 1200 ℃,保温 1h 时,样品具有较低的体积电阻率(0.03 ·cm)。  相似文献   

9.
热压烧结制备纳米Y-TZP材料形貌及结构的分析   总被引:10,自引:0,他引:10  
李蔚  高濂  李强 《硅酸盐学报》2001,29(1):84-86
研究分析了热压烧结纳米ZrO2(3Y)粉体制备的Y-TZP材料的形貌和结构。结果发现:热压烧结制备纳米Y-TZP材料有很多新的特点,最明显的包括所得样品侧面内凹、断口轴向大气孔呈梯度分布。研究结果还表明:侧面内凹的现象主要是由于纳米粉体颗粒小、比表面能大而烧结所引起的。样品断口大气孔从外向内呈梯度分布的现象不是由样品内外压差或温差造成的,而是由于样品各部分塑性滑移不均匀的结果。  相似文献   

10.
Ti-ZrO2系梯度材料的制备与显微结构研究   总被引:6,自引:1,他引:5  
采用粉末冶金法热压合成了Ti-ZrO2系梯度功能材料,用有限元法模拟了设计材料的残余热应力分布。利用扫描电镜、电子探针,透射电镜和X射线衍射等手段,对Ti-ZrO2系梯度材料组成相的分布形态、相组成以及组元之间的界面结构状态等进行了详细的研究,结果表明:合成的材料具有宏观组织不均匀性与微观组织连续性的特征,Ti-ZrO2系梯度材料由α-Ti四方相ZrO2和单斜相ZrO2组成,合成条件下组元Ti和Z  相似文献   

11.
A new polymer nanolayer gradient refractive index (GRIN) system with more robust thermal stability because of incorporation of a high glass transition temperature polyester, OKP4HT, was demonstrated. A combination of extruded nanolayered GRIN film systems, comprised of five unique polymer materials, were combined to produce laminate optics comprised of a large internal refractive index gradient distribution, n = 1.445 – 1.630, without degradation of optical transmissive properties. The optical performance of a series of varied magnitude GRIN lenses, ranging from Δn = 0 to 0.185, was evaluated. Increasing the lens refractive index range resulted in decreased optic sphericalaberrations that followed analytical predictions. An analytical approach was reported to correlate the polymer material upper service temperature (UST) to the onset of polymer material loss modulus as measured by DMTA. Thermo‐optical interferometry measurements of irreversible lens deformation confirmed the lenses UST at 125°C for the OKP4HT/PC system as compared to 75°C for a PMM/SAN17 system. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42741.  相似文献   

12.
溶胶-凝胶生物活性玻璃的纳米结构分析研究   总被引:2,自引:0,他引:2  
利用溶胶-凝胶低温合成法制备了CaO-P2O5-SiO2系统生物活性玻璃骨修复及骨组织工程材料.利用SEM、BET及XRD等方法对溶胶-凝胶生物活性玻璃的微观结构及其组成对材料微观结构的影响进行了分析,并同目前已临床应用的45S5生物活性玻璃进行了比较.研究发现由溶胶-凝胶法制备的生物活性玻璃是由纳米级微球构成,其高比表面积是由其纳米微球之间的孔隙所致.这种高比表面积对于提高材料的表面吸附能力及生物矿化功能具有重要作用.根据等大球体最紧密堆积原理建立了溶胶-凝胶生物活性玻璃纳米孔隙尺寸近似计算模型,并对其孔隙结构进行了分析计算.  相似文献   

13.
This Account describes recent work in the development and applications of sol-gel sensors for concentrated strong acids and bases and metal ions. The use of sol-gel films doped with organic indicators for the optical sensing of concentrated strong acids (HCl, 1-10 M) and bases (NaOH, 1-10 M) has been explored, and the development of dual optical sensor approaches for ternary systems (HCl-salt-H 2O and NaOH-alcohol-H 2O) to give acid and salt, as well as base and alcohol, concentrations is discussed. The preparation of transparent, ligand-grafted sol-gel monoliths is also described, and their use in the analysis of both metal cations (Cu (2+)) and metal anions [Cr(VI)] is presented. A new model using both metal ion diffusion and immobilization by the ligands in such monoliths has been developed to give metal concentrations using the optical monolith sensors. In addition to optical sensing, a method utilizing ligand-grafted sol-gel films for analyte preconcentration in the electrochemical determination of Cr(VI) has been explored and is discussed.  相似文献   

14.
The glass surface has been modified by titanium dioxide films synthesized using the sol-gel method. The sol-gel synthesis has been optimized by the experimental design with the use of the Latin square method. The film composition has been evaluated using X-ray powder diffraction analysis and optical measurements. The photoinduced hydrophilicity of the modified glass has been investigated.  相似文献   

15.
溶胶-凝胶技术制备材料的进展   总被引:113,自引:6,他引:113  
本文总结了溶胶-凝胶技术发展阶段,评述了不同溶胶-凝胶过程机制特征。着重介绍了溶胶-凝胶技术在制备块状、纤维、薄膜与涂层、粉末和复合材料方面目前的发展状况。  相似文献   

16.
Using the interfacial gel polymerization method, a heat‐resistant gradient‐index polymer optical fiber (GI POF) was developed based on the copolymer of methyl methacrylate (MMA) and N‐isopropylmaleimide (IPMI) as the matrix material and bromobenzene (BB) as dopant. The gradient distribution of IPMI in the GI POF rod was determined by element analysis. IPMI had great advantage in improving glass transition temperature (Tg) and forming a gradient‐index profile. There was a significant enhancement in the heat‐resistant property in comparison with a conventional GI POF rod. The combination of high thermal stability and easy fabrication makes the novel BB–IPMI–MMA system very suitable for heat‐resistant GI POF. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 280–283, 2003  相似文献   

17.
Summary The synthesis of new high optical abrasion resistance coating materials has been undertaken by functionalizing melamine and tris(m-aminophenyl)phosphine oxide with a triethoxysilane containing reagent. These highly functionalized compounds have been used for coating a bis-phenol-A polycarbonate substrate by the sol-gel method. Preliminary data shows the abrasion resistance of the polymer substrate is considerably improved when it is coated by these optically clear materials.  相似文献   

18.
Emerging guided-wave integrated optical technologies require suitable active devices and optical interconnects. Certain organic molecular materials possess the required optical nonlinearities for application in active devices. Glassy polymers, such as poly(methyl methacrylate), have been used to fabricate high optical quality passive structures. For application in integrated optics, requirements include high optical quality (low scattering and absorption losses), low dielectric constant, and suitable fabrication techniques. We describe the preparation and optical properties of a new material, class, poled polymer glasses, which combines the attractive properties of the optical nonlinearities of organic molecules and the optical quality of polymer glasses. These materials are formed by incorporating organic compounds possessing large optical nonlinearities into a host material lacking long-range order. The orientational order is imparted to the composite system by applying a strong electric field at a temperature above the glass transition temperature, where molecular motion is enhanced, thereby aligning the optically nonlinear dopant molecules. By cooling the material through the phase transition with the field still applied, the orientational order is frozen in, and the composite material possesses second-order nonlinear optical properties.  相似文献   

19.
以氯化钐为起始原料,采用溶胶-凝胶法在玻璃和Si(100)基板上制备了Sm2O3光学薄膜,在300~800℃对薄膜进行1~3 h热处理.采用X射线衍射、原子力显微镜和紫外-可见自记式分光光度计等对薄膜的结晶取向、显微结构和光学性能进行了表征.结果表明:Sm2O3薄膜在玻璃基板和Si(100)基板上均表现出沿(311)晶面定向生长的特征;Si基板更有利于生长致密而且结晶良好的薄膜;所制备的薄膜对紫外线有强烈吸收作用,而对可见光有较好的透过作用,随着热处理温度的升高,薄膜结晶性变好,取向性增强,光吸收性能增强,薄膜的禁带宽度减小.  相似文献   

20.
An optical quality silica glass doped with Er3+, Yb3+ and Lu3+ ions is synthesized by the sol-gel method. Virtually unavoidable clusterization of rare-earth elements that occurs upon introduction of lanthanide salts into a sol-gel system and leads to concentration quenching of luminescence of the glass is eliminated through the use of rare-earth phosphate complexes that are chemically bound to the SiO2 network. This makes it possible to obtain a nearly molecular distribution of rare-earth elements in the glass matrix.  相似文献   

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