（Ba1-xSrx）（Zn1/3Nb2/3）O3微波介质陶瓷温度系数的异常

Temperature coefficient abnormity of （Ba1-xSrx）（Zn1/3Nb2/3）O3 microwave dielectric ceramics

研究了（Ba1-xSrx）（Zn1/3Nb2/3）O3微波介质陶瓷温度系数的非线性变化以及异常的原因。根据CM公式，随着系统中Sr（Zn1/3Nb2/3）O3的增多，τc的异常是由于氧八面体的畸变导致的相转变（对称性降低）所造成的（晶体结构由无序立方相向有序赝立方相的连续变化）。相转变的发生相应影响了极化以及极化模式，这是造成τc异常的根本原因。

The paper studied non-linearity change and abnormity of temperature coefficient of （Ba1-xSrx）（Zn1/3Nb2/3）O3 microwave dielectric ceramics. It stated that abnormity of temperature coefficient （4o） is because of phase transition （symmetry dropping） caused by tilting of oxygen octahedron （crystal structure changes from disordered cubic phase to ordered pseudocubic phase continually）. Phase transition affects polarization and polarization mode and this are the essential reason that cause abnormity of temperature coefficient.