MAGNETO RHEOLOGICAL FLUID AND CLUTCH ARRANGED BY USE THEREOF

摘要

PROBLEM TO BE SOLVED: To materialize a magneto rheological fluid of a high efficiency such that a stress is sharply increased on application of a magnetic field thereto.SOLUTION: A magneto rheological fluid comprises: a magnetic particle mixture; and a dispersant with the magnetic particle mixture dispersed therein. The magnetic particle mixture includes first magnetic particles and second magnetic particles. The first magnetic particles have an average particle diameter of 1-30 μm. The second magnetic particles have an average particle diameter of 50-200 nm, and are made of a soft magnetic material. The second magnetic particles account for 10-40 mass% of the magnetic particle mixture.