摘要
用正电子湮没技术测量了 Bi-Sr-Ti-O 系介电陶瓷的正电子寿命谱.基于正电子理论,对该系样品中的寿命谱参数与材料中的缺陷机构进行了分析.结果表明,在固溶区内,当 Bi 含量较低时,材料中仅存在锶空位;而当 Bi 含量较高时,锶空位(V_(Sr))之间及锶空位(V_(Sr))与杂质 Bi_(Sr)之间可缔合成复合缺陷.另一方面,正电子寿命谱也能反映出 Bi 在 SrTiO_3中替代的固溶限.实验表明,正电子湮没技术是研究掺杂改性的介电陶瓷中微观缺陷机构的有效手段.
The positron annihilation lifetime spectra of Sr-Bi-Ti-O dielectric ceramics were measured.The positron parameters and defect structure in this ceramic system were discussed based onthe positron annihilation theory.In the solid solution region,the results show that there onlyexist strontium vacancies when bismuth content is small;and the complex-defects appear in theform of [V_(Sr)]_2 and[Vsr Bi_(sr)] as bismuth content is higher.On the Other hand,the solubilityof bismuth substitution for strontium in SrTiO_3 ceramics can be sensitively detected by thepositron annihilation technique.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
1992年第4期423-428,共6页
Journal of Inorganic Materials
关键词
介电陶瓷
正电子湮没
钛酸锶铋
Dielectric ceramics
Positron annihilation technique
Complex-defect
