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以硅(Si)粉、六方氮化硼(h-BN)为原料,在氮气(N2)中用燃烧合成(combustion synthesis,CS)气固反应法,原位生成可加工氮化硅/氮化硼(Si3N4/h-BN)复相陶瓷.考察了h-BN不同体积分数(下同)对Si3N4/h-BN复相陶瓷可加工性的影响.结果表明:在实验条件下,Si粉氮化完全,不存在残余的游离Si.Si3N4/h-BN复相陶瓷中以柱状β-Si3N4为主相,β-Si3N4晶粒之间为针状h-BN相.随着h-BN相含量的增加,Si3N4/h-BN复相陶瓷的可加工性提高,抗弯强度先减小后增加.h-BN含量为25%时,Si3N4/h-BN复相陶瓷的抗弯强度最低. 相似文献
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可加工陶瓷材料的发展 总被引:1,自引:0,他引:1
本文以可加工陶瓷的发展过程为线索,综合论述了各类可加工陶瓷材料的结构、性能及研究状况.介绍了近几年来国内外研究进展,并展望了今后的研究方向。 相似文献
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可加工氟云母玻璃陶瓷研究进展 总被引:1,自引:1,他引:0
可加工氟云母玻璃陶瓷是一种新型的结构材料,可用普通的金属刀具进行机械加工,自问世以来一直是陶瓷材料领域的一个研究热点.传统的可加工氟云母玻璃陶瓷中的主晶相是氟金云母和四硅氟云母,近年来又开发出钡云母、钙云母、锂云母和复相氟云母等新型的氟云母玻璃陶瓷,本文综述了近年来国内外在这方面的研究进展. 相似文献
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国内无机晶须在高分子复合材料中的应用研究进展 总被引:2,自引:0,他引:2
无机晶须作为一种单晶纤维材料,具有结构完整、强度高、热稳定性好等优点,是塑料、金属和陶瓷等材料的新型改性添加剂,已制成了多种耐热、耐磨、耐腐蚀等高性能材料,应用在机械、电子、汽车等领域。本文综述了硫酸镁、钛酸钾、硼酸铝、硫酸钙、氧化锌和碳酸钙等常用无机晶须的特性及其在高分子复合材料中的应用研究进展。 相似文献
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氧化物-非氧化物复合材料研究开发进展 总被引:2,自引:0,他引:2
综述了我们实验室与企业合作研究开发的冶金工业用氧化物-非氧化物复合高效耐火材料的一些进展:(1)用高温还原-氮化法研制了高炉用矾土基β-SiAlON结合刚玉复合材料,在配方基质中用矾土取代刚玉;(2)用矾土基β-SiAlON取代Al2O3-C砖中部分或全部石墨,开发了低碳Al2O3-SiAlON滑板材料,已成功用于生产高质量钢连铸;(3)研究开发了金属Al-Si复合Al2O3-C滑板材料,它具有较高的高温强度和优良的抗热震性,其特点是低碳含量、低温烧成和在高温使用时原位生成碳化物和氮化物,已成功用于优质钢连铸的钢包和中间包。 相似文献
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《Journal of the European Ceramic Society》2006,26(9):1687-1693
Using a mica-crystallizing glass powder in which a large amount of mica crystal was precipitated and a larger amount of MgF2 component was contained as the raw materials of mica, machinable alumina/mica composites were obtained at 1400 °C. In the firing process, magnesia component in the mica crystals reacted with alumina to form spinel at 1150–1200 °C. The reaction made the mica crystals melt. However, the mica crystals were precipitated again during the cooling. Because a larger amount of MgF2 component was contained in the mica-crystallizing glass powder, the nucleation of the mica crystals was caused during the cooling by the residual magnesium and fluorine in the liquid phase and succeedingly the mica crystals were precipitated. The precipitated mica crystals grew to anisotropicaly larger size than alumina grains, which lowered the bending strength and Vickers hardness and little heightened the fracture toughness. 相似文献
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Celaletdin Ergun 《Ceramics International》2011,37(3):1143-1146
Hydroxylapatite/CaTiO3 and tricalcium phosphate/CaTiO3 composites were prepared by pressureless air sintering and characterized in terms of phase stability, microstructure and pole drilling for their suitability for machining. In hydroxylapatite/CaTiO3 composites, Ti incorporation into the apatite structure caused lattice shrinkage and eventual decomposition of the hydroxylapatite associated with the formation of α-tricalcium phosphate during sintering at 1100 °C. Later, α-tricalcium phosphate disappeared at 1300 °C, possibly reacting with CaTiO3 at the expense of both phases. On the other hand, tricalcium phosphate/CaTiO3 composites were thermally stable up to 1100 °C insuring a weak interface between the components, which is one of the requirements for machinability in ceramic composites. Drilling tests also verified their suitability for machining. 相似文献