Rheological characteristics of magnetic viscoelastic fluids and their lubrication in a cone-plate magnetic coupling

Rheological characteristics of different magnetic viscoelastic fluids (MVFs) are investigated and their lubrication performances in a cone-plate magnetic coupling are examined in the present work. The test MVFs have been shown a non-Newtonian fluid behavior. Imposing magnetic field to MVFs is found to be able to change their viscosities, and this change depends on the mass ratio of the magnetic fluid in MVFs. The first normal stress difference that MVFs act on the magnetic cone of rheometer decreases with increase of the magnetic field, and it becomes negative at low shear speed. The lubrication experiment in the present produced cone-plate magnetic coupling shows that adding a small amount of the magnetic fluids into the viscoelastic liquid improves the lubrication in the magnetic coupling. All test MVFs perform well in the range of the rotating speed from 750 rpm to 1500 rpm.