金属-PTC陶瓷复合材料的介电性质

Dielectric properties of metal-PTC ceramic composite

研究了金属ＰＴＣ陶瓷复合材料的介电行为。研究表明：金属－ＰＴＣ陶瓷在电场作用下，由于正负电荷、晶格畸变和空位缺陷等而产生空间电荷极化使金属－ＰＴＣ陶瓷复合材料有较高介电常数。介电损耗（ｔｇδ）频率谱和介电常数（δ）温度谱上都出现一个介电损耗峰，其主要原因是跃迁极化，金属阳离子由一个位置跃迁到另一个位置，在介电损耗峰和介电常数峰所对应的频率和温度时出现跃迁极化率最大。

The dielectric constant behavior of the metal-PTC ceramic composite is investigated.There exist varieties of polarizations in such composite.The samples exhibit much higher dielectric constant due to space charge polarization caused by positive and negative charge and crystal lattice distortion,and vacant defect.etc.There exhibits dielectric loss peak on the frequency spectra of both dielectric loss(tg δ )and dielectric constant( δ )largely because of transition polarization during which the positive ion transition from one position to another position so that the maximum transition polarizability occurs at the frequency and temperature corresponding to the peaks of dielectric loss and dielectric constant.