纳米复合磁流变液的流变特性

在不同的磁场强度H、剪切速率γ和温度T下,测试了纳米复合磁流变(MR)液的磁致剪切应力△τ以及响应时间△tο结果表明,H、γ和T对纳米复合MR液的△t的影响较小,纳米复合MR液对撤消磁场的响应比施加磁场的响应略慢;随H增加,△τ增加;随户提高、△τ出现最大值;随T升高,△τ缓慢降低。它们之间的定量关系可用公式△τ=kHH+(Kγ1-kγ2γ)γ-kt△T来描述,其中:kH=28.32,kγ1=2.85,kγ2=0.0013,kt=3.8。用它能较全面地评价纳米复合MR液的性能,并可作为设计磁流变液智能器件的基础。

Rheological Characteristics of Nanocomposite-based Magnetorheological Suspension

The magnetic field-induced shear stress(Δτ)and the response time (Δt) for a nanocomposite-based magnetorheological (MR) suspension were determined as functions of magnetic field strength (H), shear rate (γ) and temperature (T). The results showed that Δt had almost independence of H, γ and 71 The MR suspension responded to external magnetic field a little lower at "switching off" than at "switching on" . Δτ increased with the increase of H, a maximum of Δτ occurred with increasing γ ,and Δτ slowly decreased with T. The quantity relationship among them fitted in with the equation of Δτ=kHH+( kγ1- kγ2γ) γ -ktτT very well, where kH=28.32,kγ1=2.85,kγ2=0.0013, kt=3.8 . Using this equation can characterize well the properties for the MR suspensions, which is the basis of designing MR intelligent devices.