稳恒磁场处理对聚乙烯基复合材料正温度系数特性的影响  

Effect of Static Magnetic Field Treatment on Positive Temperature Coefficient Behavior of Polyethylene Matrix Composites

作　　者：韩宝忠[1] 李长明[1] 马凤莲[1] 

机构地区：[1]哈尔滨理工大学电气与电子工程学院电介质工程国家重点实验室培育基地,哈尔滨150080

出　　处：《电工技术学报》2013年第2期55-59,共5页Transactions of China Electrotechnical Society

基　　金：国家重点基础研究发展计划(973计划)(2012CB723308);国家自然科学基金(51077030)资助项目

摘　　要：在高密度聚乙烯(HDPE)/炭黑/碳纳米管和HDPE/炭黑/铁粉复合材料的热压成型过程中施加稳恒强磁场,研究了磁场处理对HDPE基正温度系数(PTC)材料温敏特性的影响。研究结果表明:磁场处理能导致碳纳米管和铁粉在HDPE中沿外施磁场方向取向排列,使复合材料在平行磁场方向的导电性增强,从而保证在减少炭黑掺量时复合材料具有较低的室温电阻率和较大的PTC强度,其机械性能和加工性能明显改善;添加相同质量份数的铁粉和碳纳米管时,经磁场处理后,HDPE/炭黑/铁粉复合材料的PTC特性优于HDPE/炭黑/碳纳米管复合材料。A static magnetic field is applied during hot press molding of high-density polyethylene （HDPE）/carbon black（CB）/ferrous powder composites and HDPE/CB/carbon nanotube（CNT） composites. The effect of magnetic field treatment on the temperature-sensing behavior of polyethylene matrix positive temperature coefficient（PTC） composites is investigated. Experimental results indicate that the magnetic field treatment can lead to an alignment of ferrous powders and CNT in HDPE along the direction of applied external magnetic field and further enhance electrical conductivity of the composites in the direction parallel to the magnetic field. This guarantees the composites to have low room-temperature resistivity and high PTC intensity as the concentration of CB is cut down, and also can significantly improve mechanical property and processability of the composites. When the mass concentrations of ferrous powders and CNT are equal, HDPE/CB/ferrous powder composites present better PTC behavior than HDPE/CB/CNT composites after magnetic field treatment.

关 键 词：磁场 高密度聚乙烯 正温度系数材料 铁粉 碳纳米管 

分 类 号：TM243[一般工业技术—材料科学与工程]