Sedimentation evaluation of high-viscosity linear polysiloxane-based magnetorheological fluids using automated vertical axis inductance monitoring system

The sedimentation evaluation of magnetorheological fluids (MRFs) is a key component to developing successful commercial MRF-based engineering applications. In this study, the long-term sedimentation stability of highly stable high-viscosity linear polysiloxane-based MRFs (HVLP MRFs) was experimentally investigated by using an automated vertical axis inductance monitoring system (AVAIMS). The sedimentation evaluation of the HVLP MRFs with high particle loadings up to 45 vol% was tracked for 295 days, and the four different sedimentation zones such as supernatant, original concentration, variable concentration, and sediment were identified. To this end, the automated identification method to determine the sedimentation zone boundaries of highly stable MRFs was proposed. Three HVLP MRF samples with two different high particle loadings of 35 vol% and 45 vol% and two different high carrier viscosities of 5k and 10k cSt were selected as testing samples and one commercial MRF with a particle loading of 40 vol% (i.e., LORD MRF-140CG) also was tested as a baseline.