【摘要】 通过溶胶-凝胶法制备了La_1-xSr_xCrO₃纳米粉体并实现了低温致密烧结,用X射线衍射仪、透射电镜、差示扫描量热分析仪和扫描电镜对粉体和烧结体进行分析.结果表明:粉体的平均直径<50nm,当x=0,0.1时,粉体为单一的La_1-xSr_xCrO₃,x=0.3时存在第二相SrCrO₄.Sr掺杂使铬酸镧晶格产生畸变,随Sr含量的增加,晶格常数逐渐变小.铬酸镧纳米粉体的烧结分为两个阶段,1200℃以前的缓慢放热和1350℃左右的较快放热,分别对应烧结的初期和中期.依据DSC分析结果制订了烧结工艺,并在1380℃烧结得到相对密度91%的铬酸镧烧结体.更多还原

【Abstract】 La_1-xSr_xCrO₃ powders were synthesized by a sol-gel method and sintered at a low tem- perature.The powders and sintered pellets were characterized by XRD,TEM,DSC and SEM.It is found that the mean particle size is below 50nm.The powder with x=0 and 0.1 of single phase of La_1-xSr_xCrO₃,and another phase SrCrO₄ appears with x=0.3.Lattice distorts and lattice parameters of lanthanum chromite decrease with increasing Sr content.The sintering process of lanthanum chromite can be divided into two stages:a slow exothermic effect below 1200℃and a quick exothermic effect near 1350℃,corresponding to the primary and intermediate sintering stage,respectively.The relative density of the sintered body（x=0.3）after sintering at 1380℃is 91%,according to the procedure derived from the DSC analysis.更多还原