Do LORD MR fluids settle?
A. While particulate settling can occur, it can be controlled and has not been a barrier to the successful commercial application of LORD MR fluids. Most MR fluid devices such as dampers and shock absorbers are highly efficient mixing devices. As long as the MR fluid does not settle into a hard sediment, the normal motion of the device is adequate to cause sufficient flow to remix any stratified MR fluid back to a homogeneous state. LORD MR fluids can be designed to have essentially no settling when required by applications where the device is inactive for a long period of time, such as in seismic damage mitigation or automotive crash energy absorption. However a small amount of settling is typically an acceptable trade-off for other desirable properties. Much of the “art and science” of formulating MR fluids is striking a balance between low settling, low viscosity, high forces, good wear resistance, ease of filling, etc.
