摘要
采用溶胶-凝胶(sol-gel)法制备了名义组分为La0.67Sr0.20Cu0.10□0.03MnO3(□代表阳离子空位)的多晶样品母体粉体材料,在400℃下氢气环境中对母体材料进行还原处理。在不同温度下于空气中烧结不同时间得到系列块体样品。研究了热加工条件对粉体以及块体样品居里温度的影响。结果表明,发现粉体样品和块体样品的居里温度相差不多,但是随着温度的降低,块体样品的比磁化强度迅速增大,粉体样品的比磁化强度却增加缓慢;与块体样品相比,粉体样品的比磁化强度随温度降低而增加缓慢的主要原因是粉体样品晶粒小,晶粒表面原子占原子总数的比例大,而表面原子的结合较弱。
La0.67Sr0.20Cu0.10囗0.03MnO3（＂囗＂ representing cation vacancy） poly-crystalline manganite powder was synthesized by sol-gel method, which was used as parent materials. After reduced in hydrogen atmosphere at 400℃, the series bulk samples were obtained by sintering in air at different temperatures for different time. It can be found that the Curie temperature of the powder samples and bulk samples are similar. But as the temperature decreasing, the special magnetization of bulk samples rapidly increases, the special magnetization of the powder sample slowly increases. Compared with bulk samples, the special magnetization of the powder sample decreases with temperature increasing slowly, which is mainly due to the small grains of powder samples in the grain surface atoms occupying a large proportion of the total number of atoms, while the surface atoms bond poorly.
出处
《热加工工艺》
CSCD
北大核心
2013年第6期166-168,共3页
Hot Working Technology
基金
河北省高等学校科学技术研究项目(Z2012002)
河北联合大学科学研究基金资助项目(Z201216)
关键词
溶胶-凝胶法
钙钛矿结构
还原
居里温度
磁学性质
sol-gel method
perovskite structure
reducing treatment
Curie temperature
magnetic properties
