The way of producing a suspension containing silicon steel and graphite particles dispersed in a non-polymerised epoxy resin and the structure of a system for investigation of a magnetoresistance flow and a relaxation in this suspension were described. Moreover, the changes of magnetoresistance depending on time and resulting from a quick applying and switching off the magnetic field with induction of 0.3, 0.6 and 0.9 T were presented.