Study on the synthesis of corundum - mullite - gahnite multiphase materials by two - step sintering process using kaolinite as raw material showed that impurities introduced by kaolinite mainly increased the liquid amount at high temperature , which can assist sintering of specimen . the experiment results indicated that the samples with lower gahnite content had better sinterability than others . however , if the gahnite content was relative high , the promoting effect on sinterability caused by kaolinite was not significant 采用天然原料高岭土二步煅烧合成刚玉?莫来石?锌铝尖晶石复相材料研究发现：天然原料中带入的杂质主要是增加液相量，促进高温下试样的烧结；当尖晶石含量较低时，试样在1300保温2h时，在1600烧后试样烧结性能相比之下较好；而当锌铝尖晶石含量较高时，天然料对试样的促烧作用不是非常明显。
The physical properties were measured using x ray diffraction analyzing , sem observing , fracture toughness and fracture strength measuring , micro - hardening and density detection etc . the results display that the relative densities are above 98 % for all the samples , especially reaches 99 . 8 % for the sample added 2vol % sic nano - particles 在sic加入量为2vol %时，由于分散比较均匀，对样品烧结性能影响不大，相对密度可达99 . 8 % 。在未加sic时，四方zro2的含量最高为50 . 5vol % 。随sic加入量的增加，四方相zro2的含量呈下降趋势。
In the process of making 95 alumina ceramics , selected five kinds of alumina powder and studied the influence of different alumina powder on the sintering properties and mechanic properties of 95 alumina ceramics , moreover , selected the most agreeable alumina powder according to the apparatus for granularity analysis and scanning electron microscope ( sem ) . the influence of different sintering temperature on the sintering mechanic properties , the microstructure of 95 alumina ceramics were investigated by adding y2o3 and la2o3 as two kinds of rare earth additives in alumina ceramics . the results indicated that the additive of la2o3 could improve the properties of 95 alumina ceramics more effectively and could get fine grain and tabular alumina that can enhance the strength of the material 选用了五种al2o3粉料，研究了其对95al2o3瓷烧结性能和力学性能的影响，并结合粒度分析仪sem对al2o3粉料进行优选；通过添加y2o3 、 la2o3两种稀土添加剂，研究了不同烧成温度对95al2o3瓷的烧结性能、力学性能及显微结构等的影响，结果表明：添加la2o3可以有效提高95氧化铝瓷烧结性能和力学性能，形成细晶和板状氧化铝瓷的显微结构；通过对比不同氧化铝粉料制备氧化铝瓷烧成温度曲线与烧结性能的关系，确定最佳的烧成温度范围为1570 ~ 1600 。
It was found that ball milling the precipitates and the reduced w - cu powder can further reduce the particle size and improve the distribution of w and cu ingredients in the final w - cu powder . this results in both the increase of sintered density and property , and the improvement of microstructure of the w - cu composites 其中，共球磨处理的w一cu复合粉末( hp一m )压坯在1150下烧结90min所获烧结体具有最好的烧结性能，其硬度、抗弯强度和电导率分别为325 . 58mpa 、 1106 . 62mpa和42 . 99 % 。
Perovskite - type complex oxides of la1 - xcaxcro3 compositions are attracting growing attention because of their superior electronic conductivity and excellent chemical stability in both oxidizing and reducing atmospheres , which makes them promising candidate materials for many important applications , such as interconnectors for solid oxide fuel cells ( sofc ) , heating elements for high temperature furnaces , and current collecting electrodes in magneto - hydrodynamics ( mhd ) . in this dissertation , the gnp ( glycine - nitrate process ) method has been employed to synthesize la1 - xcaxcro3 oxides . the synthesis and preparation , sinterability , electrical conducting properties and thermal expansion properties of la1 - xcaxcro3 oxides have been investigated 本文采用gnp ( glycine - nitrateprocess )法制备了la _ ( 1 - x ) ca _ xcro _ 3材料，对制备方法与工艺参数、材料烧结性能、电性能以及热膨胀性能进行了研究，分析了ca ~ ( 2 + )含量、粉体颗粒形态对材料烧结行为、烧结致密化温度的影响，并研究了ca ~ ( 2 + )含量、粉体颗粒形态对材料晶体结构、显微结构和物理性能的影响，其目的在于为该类高温电子导体的进一步研究利应用提供实验和理论依据。
