蒸汽掺杂-一种新的钛酸钡基PTCR陶瓷的掺杂方法

Vapor Doping Method, a New Effective Method Used in BaTiO_3 Based PTCR Ceramics

晶界效应是陶瓷材料所固有的特性．利用某些氧化物在高温下具有较高的蒸汽压，在烧成过程对陶瓷材料进行掺杂改性，可以有效地控制晶界行为，改善材料性能．钛酸钡基半导化陶瓷中存在的PTCR效应；是一种典型的晶界效应．利用Sb2O3、Bi2O3蒸汽掺杂的钛酸钡基PTCR材料，晶粒细小、均匀致密、升阻比可以做到大于8个数量级．因而，蒸汽掺杂是一种新型高效的掺杂方法．

Grain boundary effect is one of the characteristics of ceramic materials. Some oxides have high vaporization pressure. Using vapor as doping resource during sintering, the grain boundary behavior can be effectively controlled and the material properties can be improved. The PTCR effect that existed in semiconducting barium titanate based ceramics is a typical grain boundary effect. The experimental results show that materials doped with Sb2O3 or Bi2O3 vapor have high density and homogeneous microstructure with small grain size. The sample with over 8 orders of magnitude degree of resistivity jumping can be obtained. Thus vapor doping method is a new and effective method.