颗粒尺寸对注塑铁氧体/尼龙12复合材料流动性和磁性能的影响

Influence of particle size on the fluidity and magnetic properties of ferrite/nylon-12 composites for injection molding

制备颗粒尺寸不同的铁氧体磁粉,采用混炼工艺制备铁氧体/尼龙复合材料,研究了颗粒尺寸对复合材料流动性和磁性能的影响,结果表明,当铁氧体大小颗粒尺寸之比大于4时,两者级配可以使复合体系获得最佳的流动性。对颗粒尺寸影响机理的研究表明,小颗粒的尺寸下限在0.5?m附近,大颗粒尺寸上限在5?m附近,当大、小颗粒及尼龙体积分数分别在52～31vol%、15～36vol%和33vol%时,铁氧体/尼龙复合体系可以获得最佳的流动性和高的磁性能。

Ferrite powders of different particle size and nylon/ferrite composites were prepared using blending techniques. The influence of particle size on the fluidity and magnetic properties of the composite system was investigated. The results showed that the composite system has the best fluidity when the big particle size is over four times than that of the small particles. The study on the mechanism of particle size effects showed that in the composite system the lower limit of small particle size and the top limit of big particle size are about 0.5μm and 5μm, respectively. The good fluidity and high magnetic properties can be achieved in the ferrite/nylon 12 composites in the range of 52-31vo1% big particles, 15-36vo1% small particles, and 33vo1% nylon 12.