镍粉/环氧树脂复合材料的压敏性

探讨了镍粉/环氧树脂复合材料电阻率的测试方法,研究了不同镍粉掺量、不同柔韧性环氧树脂掺量的镍粉/环氧树脂复合材料在单轴压缩下的电阻率变化规律,并结合镍粉/环氧树脂复合材料的静态电阻率和压力下的体积变化讨论了其压敏性产生机理.研究结果表明:采用直流两端电极法与直流四端电极法所测得的镍粉/环氧树脂复合材料的电阻值较为一致,...

Piezoresistivity of Nickel Powder Filled Epoxy Resin Composites

The measurement method of electrical resistivity of nickel powder filled epoxy resin composites was explored.The variation regularity of electrical resistivity of nickel powder filled epoxy resin composites with different contents of nickel powder and flexible epoxy resin under uniaxial compression was studied.The generation mechanism of piezoresistivity of nickel powder filled epoxy resin composites was discussed according to static electrical resistivity and variation in volume of composites under compression.The research results show that the electrical resistance of composites measured with the direct current two-electrode method is consistent with that measured with the direct current four-electrode method,which indicates that the direct current two-electrode method is feasible for measurement of electrical resistivity of this kind of composites.The fabricated nickel powder filled epoxy resin composites have good piezoresistivity.The absolute value of the fractional change in electrical resistivity reaches 69.98% maximum under compressive stress in a range from 0MPa to 12.5MPa.The sensitivity of piezoresistivity of nickel powder filled epoxy resin composites increases when the content of nickel powder decreases and the content of flexible epoxy resin increases.The generation of piezoresistivity of this kind of composites is due to the enhancement of tunnel effect,which is caused by the decrease in volume of composites under compression.