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为使NiFe2O4磁流体应用于液压传动领域,一定程度解决叶片泵中的磨损问题,需研究其黏度特性.首先在无磁场条件下,参考相关液压元件对介质的黏度要求,探究分散剂、降黏剂、温度、黏度计转子转速等对磁流体黏度的影响.研究得出,选用油酸、十二烷基硫酸钠作为分散剂.乙二醇作为降黏剂,其中两种分散剂物质的量均与磁性微粒相等,且磁性微粒和乙二醇质量分数分别为3％～6％和6％～14％时,可满足黏度要求.然后,从中选出浓度最大的样品,探究磁场作用下磁感应强度、温度和磁场作用时间等对黏度及黏度比的影响.结果表明,黏度随磁感应强度增加而增大,随磁场的变化具备滞后性;黏度比随温度增加表现为先减后增规律;在一定磁场作用5000 s内,黏度基本保持稳定.“,”In order to make the application of NiFe2O4 magnetic fluid in the field of hydraulic transmission and, to some extent, solve the wear problems in vane pump, viscosity properties of the fluid ought to be studied. Firstly, referring to the requirement concerning medium's viscosities related to the hydraulic component, the effect of factors, including dispersant agents, viscosity reducers, temperature, rotational speed of viscometer, etc, on the fluids' viscosity, were investigated. In the experiment, when choosing oleic acid and sodium lauryl sulfate as dispersant agents whose amount of substance is respectively equal to that of magnetic nanoparticles, ethylene glycol as viscosity reducer, meanwhile, the mass fraction of the nanoparticles and glycol is 3％～6％ and 6％～14％ respectively, the samples can meet the requirement. Afterwards, the MF with maximal concentration was selected from the samples. The influence of factors, including magnetic flux density, temperature, viscosity, action time of magnetic field, etc, on viscosity and viscosity ratio of the fluid, were probed in the field. According to the results, viscosity of the fluid increases with increase of the density, and the viscosity possesses hysteresis with change of the field; Viscosity ratio of magnetic fluid decreases with the increase of temperature and then increases; Viscosity value of MF almost maintains stable in constant magnetic field for 5000 s.