Magnetorheological fluids with an additive package

摘要

One embodiment of the invention includes an MR fluid of improved durability. The MR fluid is particularly useful in devices that subject the fluid to substantial centrifugal forces, such as large fan clutches. A particular embodiment includes a magnetorheological fluid including 10 to 14 wt % of a hydrocarbon-based liquid, 86 to 90 wt % of bimodal magnetizable particles, 0.05 to 0.5 wt % fumed silica, and an additive package including a paraffin oil, a phenol and a sulfide.