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陶瓷燃烧器用莫来石-堇青石组合砖的研制 总被引:1,自引:0,他引:1
以烧结莫来石、电熔莫来石、合成堇青石和电熔白刚玉为主要原料,通过浇注-离心成型工艺生产了莫来石-堇青石组合砖,并研究了堇青石的加入量和加入形式对莫来石-堇青石组合砖性能的影响。结果表明:采用浇注-离心成型工艺生产的热风炉陶瓷燃烧器用组合砖的性能指标优于机压成型的同类产品;随着试样中堇青石含量的增加,制品的荷重软化开始温度逐渐降低,抗热震性逐渐提高,但在堇青石加入量(质量分数,下同)为15%时,其荷重软化开始温度和抗热震性指标都比较好;当颗粒加入量为12%,细粉加入量为3%时,制品的抗热震性最好,耐压强度也较高。产品在广州钢铁企业集团有限公司等钢厂的陶瓷燃烧器上进行了使用试验,用户反映该组合砖强度高,整体性好,能满足大、中型热风炉燃烧器使用需要,值得大力推广。 相似文献
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为满足锂离子电池正极材料烧成的需要,以堇青石、莫来石、高岭土和氧化铝为原料制备堇青石-莫来石窑具材料,研究了堇青石颗粒和细粉加入量对堇青石-莫来石窑具材料的常温性能、高温抗折强度和抗热震性的影响.并用XRD和SEM分析了试样烧后的物相变化与显微结构.结果表明:随着堇青石颗粒或细粉加入量从0到30%(质量分数),试样的线变化率、显气孔率、高温抗折强度增大,体积密度下降;而对常温抗折强度的影响不大,试样的耐压强度分别呈现下降或提高的趋势,试样的抗热震性先增加后降低,当堇青石颗粒含量为20%,细粉含量为20%时,试样的抗热震性最好. 相似文献
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以耐火粘土、高铝矾土及滑石为原料研制了堇青石基陶瓷材料,并对其组织和性能尤其是抗热震性进行了研究。结果表明,堇青石基体上分布着外状莫来石的材料具有更高的抗热震性。对换热器用陶瓷材料抗热震性参数进行了讨论,指出抗热震损伤多数R''更适合于作为优选陶瓷换热器用材料的指标。 相似文献
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为了改善高温气体过滤器支撑体的强度及抗热震性能,根据复合材料韧化强化原理,本试验采用陶瓷材料复合技术,制备莫来石-刚玉-钛酸铝-堇青石复合陶瓷材料,探索其作为高温过滤器支撑体的可能性.以粒径小于74μm的高铝矾土熟料、钛酸铝、堇青石为原料,以聚乙烯醇的溶液(质量浓度2%)为结合剂,试样成型压力为50MPa,烧结温度为1360℃,保温3小时制备了莫来石-刚玉-钛酸铝-堇青石复合材料.对烧后试样进行体积密度、气孔率、常温抗折强度、抗热震性的测定及XRD、SEM的分析,研究了配料组成对复合材料烧结及抗热震性能的影响.研究结果表明:具有较好烧结性能与抗热震性能的莫来石-刚玉-钛酸铝-堇青石复合材料支撑体的最佳物料配比(%)为:高铝矾土熟料30%、钛酸铝10%、堇青石60%. 相似文献
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评价了用于热机械设备的传统型堇青石-莫来石陶瓷中堇青石合成烧结熟料的适用性。制备了两种堇青石合成烧结熟料和传统的莫来石合成熟料。按照50:50和70:30的比例,将具有中颗粒和/或粗颗粒的堇青石合成烧结熟料与具有中颗粒和,或细颗粒的莫来石进行混合,然后在1350℃进行煅烧来生产传统的堇青石-莫来石料球。评价了与其成分和显微结构相关的物理性能。这些性能包括线性变化、体积密度、显气孔率、荷重软化点以及抗热震性。 相似文献
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加速量热仪在锂离子电池热安全性研究领域的应用 总被引:2,自引:0,他引:2
加速量热仪(Accelerating RateCalorimeter,简称ARC)是用于危险品评估的新型热分析仪器,可以提供绝热条件下化学反应的时间、温度、温升速率和压力数据。本文着重介绍了加速量热仪应用在锂离子二次电池热安全性研究方面的研究成果,总结了锂离子二次电池的正负极材料、电解液和粘结剂等对锂离子二次电池热安全性的影响,并对ARC在离子电池热安全性研究发展方向的应用进行了展望。 相似文献
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综述了导热胶粘剂的导热机理、导热模型以及提高胶粘剂导热性能的途径;详细介绍了非绝缘导热胶粘剂和绝缘导热胶粘剂的技术研究与应用,最后对导热胶粘剂的发展前景作了展望。 相似文献
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为了适应测量热老化橡胶的导热率,改进了传统的稳态法测定导热率的测量方法.用该方法测量了热老化橡胶的导热率,并对热老化橡胶的导热率的变化机理进行了初步探讨. 相似文献
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Synthesis and thermophysical properties of RETa3O9 (RE = Ce,Nd, Sm,Eu, Gd,Dy, Er) as promising thermal barrier coatings 下载免费PDF全文
Lin Chen YeHua Jiang XiaoYu Chong Jing Feng 《Journal of the American Ceramic Society》2018,101(3):1266-1278
Thermal barrier coatings (TBCs) are one of the most important materials in gas turbine to protect the high temperature components. RETa3O9 compounds have a defect‐perovskite structure, indicating that they have low thermal conductivity, which is the critical property of TBCs. Herein, dense RETa3O9 bulk ceramics were fabricated via solid‐state reaction. The crystal structure was characterized by X‐ray diffraction (XRD) and Raman Spectroscope. Scanning electron microscope (SEM) was used to observe the microstructure. The thermophysical properties of RETa3O9 were studied systematically, including specific heat, thermal diffusivity, thermal conductivity, thermal expansion coefficients, and high‐temperature phase stability. The thermal conductivities of RETa3O9 are very low (1.33‐2.37 W/m·K, 373‐1073 K), which are much lower than YSZ and La2Zr2O7; and the thermal expansion coefficients range from 4.0 × 10?6 K?1 to 10.2×10?6 K?1 (1273 K), which is close to La2Zr2O7 and YSZ. According to the differential scanning calorimetry (DSC) curve there is not phase transition at the test temperature. Due to the high melting point and excellent high‐temperature phase stability with these oxides, RETa3O9 ceramics were promising candidate materials for TBCs. 相似文献
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PA66导热绝缘塑料的制备与性能 总被引:3,自引:0,他引:3
通过尼龙66(PA66)与大粒径MgO共混经双螺杆挤出机挤出制备了导热绝缘塑料。研究了热导率与MgO填充量的关系。该导热绝缘塑料的热扩散系数和热导率随MgO填充量的增加而增大。在MgO填充量达到70%时,热导率达到1.9 W/(m.K),同时仍保持较好的力学性能和一定的电绝缘性能。热失重分析表明,该导热绝缘塑料的热分解温度受MgO填充量的影响,有约10℃的变化,低填充量(40%和50%)时,因MgO具有良好的导热性能,试样中的PA66几乎完全被分解汽化。 相似文献
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J. Chojnowski J. Kurjata S. Rubinsztajn M. Scibiorek M. Zeldin 《Journal of Inorganic and Organometallic Polymers》1992,2(4):387-404
Thermal decomposition of poly[oxybis(dimethylsilylene)] having chains terminated with trimethylsiloxy groups was studied by thermogravimetry, pyrolysis-mass spectrometry, and infrared spectroscopy. The polymer is thermally less stable than poly(dimethylsiloxane). Depolymerization occurs at temperatures of 250–350°C, although this process also takes place at lower temperatures. The depolymerization produces cyclic oligomers of general formula [(Me2Si)2O]
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, with predominant formation of the oligomern=2. The depolymerization is accompanied by processes which are referred to as restructurization because they change the structure of the polymer backbone. Decomposition may lead also to the formation of branching points. The shape of the thermograms taken under isothermal conditions is in agreement with an unzipping mechanism for depolymerization involving random initiation. Excluding the short initial period of the process, the unzipping is terminated at a restructurization point. A low activation energy points to initiation induced by electron transfer, presumably involving traces of contaminant. At higher temperatures, 350–600°C, loss of organic parts of the polymer takes place along with further restructurization. At higher temperatures the polymer was also found to undergo easily oxygenation of its backbone with atmospheric oxygen, which leads to the formation of siloxane groups. 相似文献
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This paper presents the results of thermal expansion measurements of mortar and limestone aggregate and thermal induced mesocracks around limestone aggregate in normal concrete exposed to high temperature, up to 800°C. The former was measured by a fused silica Workhorse Dilatometer. The later was observed by the viewfinder of Polarizing Optical Microscope. The results showed that the difference in coefficient of thermal expansion between mortar and limestone exhibited the temperature dependence. Thermal induced tensile stress around limestone aggregate first took place, following the hydrostatic compression under higher temperature. During the whole heating process, the tangential, radical and linkage mesocracks in concrete gradually initiated and propagated for the response of thermal induced stress around limestone aggregate. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献