Ni、Mn 加入量及工艺对PTCR复合材料的性能影响

Effects of metal contents ( Ni| Mn) and processing on PTCR ceramic properties

摘要: 采用传统固相法工艺, 在BaTiO₃基材料中加入金属Ni 、金属Mn , 制备PTCR 陶瓷复合材料, 以降低其室温电阻率。考查了金属Ni 、金属Mn 的加入量, 以及后期热处理时间和温度对复合材料性能的影响。研究表明: 在还原气氛中烧结(1250 ℃, 保温20 min) , 室温电阻率较低, 但只有很弱的PTC 效应, 再通过适当的后期热处理工艺(空气气氛, 780 ℃, 保温60 min) , PTC 效应可得到部分恢复。最终获得了具有较低的室温电阻率(ρ25 ℃= 10. 2Ω·cm) 和较高升阻比(ρmax /ρmin = 1. 42 ×10³ ) 的PTCR 复合材料。

Abstract: In order to obtain a low resistivity and high PTC effect , the Ni/ Mn/ BaTiO₃ composite was prepared bythe t raditional solid-crystal sintering method. The effect s of metal content s (Ni , Mn) and heat t reatment techniqueson positive temperature coefficient resistor ( PTCR) ceramic properties were studied. The very weak PTC effect ofthe composite sintered in deoxidizing atmosphere (1250 ℃, 20 min) was renewed effectively by heat-t reatment in air(780 ℃, 60 min) . The Ni/ Mn/ BaTiO₃ composite has the low room-temperature resistivity (ρ25 ℃ = 10. 2Ω·cm) andan obvious PTC effect (ρmax /ρmin = 1. 42 ×10³ ) .