PP/活化炭黑复合材料磁致伸缩与交流电性能

炭黑微粒子进行活化处理后,以10％(质量分数)的比例填加到聚丙烯基体中制备了复合材料,对其进行交流电性能和磁致伸缩性能测试.测试结果表明,聚丙烯/活化炭黑复合材料同时具有导电性能和磁致伸缩性能.复合材料交流电性能参数随频率的变化规律表明活化炭黑在聚丙烯基体中已形成导电网络.复合材料磁致伸缩性能测试过程中发现了3个现象:这种复合材料具有较大的磁致伸缩应变,最大的磁致伸缩应变为1.15×10^-4(115ppm);复合材料的磁致伸缩应变与磁场强度有关,这与传统的无机磁致伸缩材料相似,与之不同的是,此复合材料的磁致伸缩性能还与时间间隔有密切的关系;复合材料的磁致伸缩性能具有非常明显的滞后效应,而通常被认为是典型磁致伸缩材料的无机物Tb_xDy_1-xFe_2-y则不具有这种效应.

Magnetostrictive properties and AC electrical properties of activated carbon black filled polypropylene composites

Carbon black was activated and then filled into polypropylene to prepare composites, of which the alternating current (AC) electrical properties and the magnetostrictive properties were measured. It is shown that there are both conductive properties and magnetostrictive properties in the composites. The variation of AC electrical properties as a function of frequency shows that the conduction network of carbon black has been formed in the composites. Three phenomena could be observed during the course of the magnetostriction measurement. The first is that a relative large magnetostriction value of 115ppm is obtained. The second is that the magnetostriction is strongly dependent on the applied magnetic field and time interval. And the third is that obvious hysteresis effect appears,which is seldom found for material of Tb xDy 1-xFe 2-y considered as typical magnetostrictive material.