不同pH值下水基Ni_(0.5)Zn_(0.5)Fe_(2)O_(4)磁流体的沉降稳定性分析

Sedimentation Stability of Water Based Ni_(0.5)Zn_(0.5)Fe_(2)O_(4) Magnetic Fluid at Different pH Values

为了深化水基磁流体的沉降稳定性研究,对水基Ni_(0.5)Zn_(0.5)Fe_(2)O_(4)磁流体在不同pH值下的沉降稳定性进行了测定,并对试验结果进行分析。研究结果表明OA(油酸)质量分数为4%、SDS(十二烷基硫酸钠)质量分数为3%、Ni_(0.5)Zn_(0.5)Fe_(2)O_(4)质量分数为2.5%时,制备的磁流体稳定性最好。当pH<7时,磁流体的沉降稳定性随着pH值的减小而降低,黏度随着pH值的减小而增大;当pH>7时,磁流体的沉降稳定性随着pH值的增大而降低。该磁流体具有良好的热分散性,温度越高磁流体的分散性越好,pH值对磁流体的热分散性有一定的影响。pH值对磁流体的磁场沉降稳定性和磁黏特性有重要影响,在恒定或递增磁场的作用下,磁流体的沉降系数和黏度随磁场和pH值的变化而变化。

In order to research the sedimentation stability of water-based magnetic fluid,the sedimentation stability of water-based Ni_(0.5)Zn_(0.5)Fe_(2)O_(4) magnetic fluid at different pH values was studied,and the experimental phenomena were analyzed.The results show that when the mass fraction of OA(oleic acid)is 4%,the mass fraction of SDS(sodium dodecyl sulfate)is 3%,and the mass fraction of Ni_(0.5)Zn_(0.5)Fe_(2)O_(4) is 2.5%,the magnetic fluid as-prepared has the best stability.When pH value is<7,the sedimentation stability of magnetic fluid decreases with the decrease of pH value,but the viscosity increases with the decrease of pH value.When pH is>7,the sedimentation stability of MHD decreases with the increase of pH value.The higher the temperature is,the better the dispersion is.The pH value has a certain influence on the thermal dispersion of the magnetic fluid.The pH value has an important influence on the magnetic field settling stability and magnetic viscosity of magnetic fluid.Under the action of constant or increasing magnetic fields,the settling coefficient and viscosity of magnetic fluid change with the change of magnetic field and pH value.