共查询到19条相似文献,搜索用时 109 毫秒
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以溶胶–凝胶法制备的钛酸铝前驱体和固相合成法制备的纳米Fe2O3为原料,在不同温度煅烧保温2h制备出钛酸铝固溶体[Al2(1–x)Fe2xTiO5]。通过X射线衍射、电子探针分析并计算晶格常数和热分解率,研究了纳米Fe2O3含量以及烧成温度对烧后试样热分解性能的影响。结果表明:纳米Fe2O3很容易与Al2TiO5反应,形成固溶体,抑制钛酸铝陶瓷的热分解;随着纳米Fe2O3加入量的增加,Al2(1–x)Fe2xTiO5的晶格常数变大,热分解率降低,但当加入量超过10%时,Al2(1–x)Fe2xTiO5的晶格常数不变甚至减小,热分解率反而会增大;纳米Fe2O3作为添加剂可改善钛酸铝陶瓷的热分解性能。煅烧温度对钛酸铝的热分解率有很大影响,随着温度升高,热分解率降低,当温度大于1350℃时,钛酸铝陶瓷晶格常数保持不变,钛酸铝陶瓷的热分解率变化不大。 相似文献
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本文详细研究了通过在钛酸铝陶瓷材料中添加滑石、叶腊石、锆英石等天然原料,而对钛酸铝热学性能和机械强度的影响关系。研究发现:添加适量的滑石、叶腊石、石英均能保持钛酸铝的低膨胀特性,且不同程度地抑制了钛酸铝的热分解,抗弯强度可高达52.9MPa。 相似文献
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复合添加剂抑制钛酸铝热分解的作用及其机理的研究 总被引:5,自引:0,他引:5
本文采用X衍射分析,热膨胀分析,透射电镜和电子探针分析详细研究了复合添加剂抑制钛酸铝热分解的作用和机理。研究表明,复合添加剂抑制钛酸铝热分解的效果比单一添加剂的效果更为显著。复合添加剂不仅提高了钛酸铝的热稳定性,而且还保持了其优良的低膨胀特性。 相似文献
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本文作者运用先进的X-射线衍射仪、扫描电镜(SEM)、能谱仪(EDX)等测试手段,对钛酸铝莫来石复合材料的显微结构、热分解性能及热膨胀特性作了详细研究;研究结果表明,不同晶形或以不同方式制备的莫来石都能有效地抑制钛酸铝晶体的高温(1000℃,200小... 相似文献
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采用拟薄水铝石和非晶态超细SiO_2微粉为原料。以溶胶-凝胶工艺制取莫来石凝胶,通过干燥、煅烧研制得片状结晶莫来石粉。初步研究了凝胶法莫来石粉在钛酸铝陶瓷和烧结刚玉砖中的应用。实验结果表明:凝胶粉起到了促进烧结、降低烧成温度的作用,并使钛酸铝——莫来石复相陶瓷和刚玉砖的强度得到了显著提高。 相似文献
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钛酸铝基复相材料的研究 总被引:3,自引:0,他引:3
研究了引入莫来石和二氧化锆复合相对钛酸铝烧结性能及抗热震性能的影响。借助SEM分析了材料的断口形貌,从显微结构上解释了Al2TiO5基复相材料热震后的断裂机制。 相似文献
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Neal R. Brodnik Katherine T. Faber 《International Journal of Applied Ceramic Technology》2019,16(3):1173-1183
This study characterizes the flexural and compressive behavior of two porous ceramic honeycombs commonly used in diesel particulate filtration, acicular mullite and aluminum titanate. Compression along the axis normal to the honeycomb cross-section, referred to as out-of-plane compression, is compared to in-plane flexure. The relationship between these loading modes is assessed using the failure strength and elastic modulus of the honeycomb structure and the constituent wall material. Weibull analyzes showed that flexure and out-of-plane compression exhibit similar behavior in cases where failure is governed by a single flaw, such as in acicular mullite. However, in heavily microcracked systems like aluminum titanate, compressive failure occurs by damage accumulation rather than growth of a single flaw, so compressive failure strengths are higher than flexural ones. Buckling was also shown to occur in both systems, but the geometries required are unlikely to be encountered in practical application. In the context of filter life assessment, failure in flexure occurs at much lower stresses for systems that rely on microcracking to accommodate thermal strains, so flexure is better suited as an estimate of filter strength. 相似文献
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MnO_2和Fe_2O_3对氧化铝质压裂支撑剂微观结构和抗破碎能力的影响(英文) 总被引:1,自引:1,他引:0
采用无压烧结技术制备了软锰矿掺杂的高强度氧化铝质压裂支撑剂.通过X射线衍射、压汞式孔隙分析、扫描电子显微镜和筒压法分别研究了由软锰矿引入的MnO2和Fe2O3对支撑剂物相组成、孔结构、晶粒尺寸和抗破碎能力的影响.结果表明:当软锰矿掺杂量为0~5%(质量分数,下同)时,烧结样品中包括氧化铝、莫来石和钛酸铝相,软锰矿的掺入未明显改变晶体结构;当软锰矿掺量为5%时,Fe3+取代Al3+与组分中的TiO2反应并形成固溶体,MnO2固溶于Al2O3晶粒中,促进了Al2O3晶粒生长,过剩的Fe2O3和MnO2存在于陶瓷晶界处并在高温煅烧F形成液相促进致密化烧结;未掺杂样品中存在大量连通气孔,显气孔率为14.79%:掺入5%软锰矿后,显气孔率降低至5.29%,样品内部多为均匀分布的近球形闭气孔;在52MPa压力条件下,5%软锰矿掺杂样品的破碎率与未掺杂样品相比减少80.95%,抗破碎能力显著提高. 相似文献
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Xuehui Huang Xinke Yang Xuefang Wang 《International Journal of Applied Ceramic Technology》2023,20(5):2974-2984
Using Al2O3 and TiO2 as raw materials, adding MgO as heat stabilizer and mullite as enhancer, aluminum titanate-mullite multiphase ceramics were successfully prepared by solid phase synthesis. The effects of MgO and mullite were systematically studied on the phase composition, microstructure, thermal stability, sintering properties, and mechanical properties of aluminum titanate ceramics. The results showed that the introduction of Mg2+ can partially replace Al3+ to form MgxAl2(1-x)Ti(1+x)O5 solid solution, improved the thermal stability of aluminum titanate ceramics, and promoted the formation and growth of grains, which reduced the sintering temperature. The crack deflections caused by mullite particles improved the mechanical properties. The filling effect of mullite particles and the formation of silica in mullite raw materials were conducive to ceramic densification. The statistics of Mg4M10 sample were as follows: the porosity was only 2.9%, the flexural strength was as high as 64.15 MPa, and the thermal expansion coefficient was 1.35 × 10−6 K−1 (RT-700°C), encouraging the application of ceramics with high thermal mechanical properties. 相似文献
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S. A. Suvorov V. N. Fishev D. B. Shadricheva T. V. Firsanova N. V. Alekseeva I. V. Ivanova T. S. Nilova 《Refractories and Industrial Ceramics》2003,44(5):330-337
Binary and ternary fused compositions based on alumomagnesian spinel, aluminum titanate, and mullite are studies using various techniques of physicochemical analysis. The minimum incipient melting temperature in the MgAl2O4 – Al6Si2O13 – Al2TiO5 system is [1645 ± 15] °C. Fused materials with tailored phase compositions are obtained under industrial conditions. Technological properties of a fused composite corundum – alumomagnesian spinel – mullite – aluminum titanate are studied. 相似文献
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引入10%(摩尔分数,相对于A12O3,下同)MgO和15%SiO2双组分添加剂合成了钛酸铝粉体.采用不同质量比的钛酸铝粉体和工业莫来石,用干压和注凝成型工艺制备了莫来石-钛酸铝(mullite-aluminium titanate,MAT)复相陶瓷.用X射线衍射分析了双组分添加剂对钛酸铝相组成和热稳定性的影响.通过扫描电镜表征了MAT复相陶瓷的微结构.研究了钛酸铝含量对采用于压、注凝2种成型工艺制备的MAT复相陶瓷的弯曲强度和平均热膨胀系数(室温~1 000℃)的影响.结果表明:MgO和SiO2双组分添加剂促进了钛酸铝的形成,增强了钛酸铝的热稳定性.通过注凝成型制备的MAT复相陶瓷比于压成型制备的MAT复相陶瓷具有史均匀的结构和更高的机械性能.当铸酸铝含量为lO%(质量分数,下同),运用注凝成型工艺 制备的MAT复相陶瓷的弯曲强度最大,达110.05 Mpa. 相似文献