Ferrofluids, or magnetic liquids, are stable colloidal suspensions of single domain particles of ferromagnetic or ferrimagnetic materials. They have existed for more than sixty years but the concentrated fluids that are used today first appeared in 1965. Ferrofluids consist of very small magnetic particles held in suspension in a carrier liquid by a surface active layer. The carrier liquid is selected to meet the particular application and can be a hydrocarbon, ester, perfluoropolyether, water, etc.

Liquids Research Limited can offer a wide range of ferrofluids in which the magnetic particles are one of a variety of ferrites or transition metals, such as iron and cobalt.