激光冲击波对ZnO压敏陶瓷电学性能的影响

为了研究激光冲击处理对ZnO压敏陶瓷电学性能的影响,采用Nd:YAG激光器对ZnO压敏陶瓷进行激光冲击处理,利用压敏电阻直流参量仪（CJ1001型）测量材料电学参量和X射线衍射仪、电子扫描显微镜表征相组成及微观形貌,取得了激光冲击处理前后ZnO压敏陶瓷电学性能的实验数据。结果表明,ZnO压敏陶瓷经激光冲击处理后,电位梯度降低了15.6%;非线性系数大幅提高了43.4%;漏电流降低了50%;同时,ZnO压敏陶瓷相组成除高温烧结态(包括ZnO主晶相、Zn2.33Sb0.67O4尖晶石相以及-Bi2O3相)外,而还出现了新相-Bi2O3相。新相的出现是材料电学性能变化的根本原因。

Effect of laser shock wave on electrical property of ZnO varistor ceramics

In order to study the influence of laser shock on the electrical property of ZnO varistor ceramics, ZnO varistor ceramics was shocked by an Nd:YAG laser. Electrical parameters of ZnO varistor ceramics were measured with a CJ1001 varistor tester and morphology and microstructure of ZnO varistor ceramics was characterized by X-ray diffraction and scanning electron microscope. The experimental data of electrical property of ZnO varistor ceramics was obtained by laser shock process. The results indicate that after laser shock processing, the voltage gradient of ZnO varistor ceramics was reduced by 15.6%; its nonlinear coefficient substantially increased by 43.4% and leakage current reduced by 50%. Phase composition of ZnO varistor ceramics includes mainly ZnO main phase, Zn2.33Sb0.67O4 phase and -Bi2O3 phase in high-temperature sintering. However, it include not only the former three phases, but also the new phase -Bi2O3 phase after laser shock process. The emergence of the new phase is the main cause for change of the electrical property of ZnO varistor ceramics.