Properties of Durable Magnetorheological Elastomers

Magnetorheological elastomers (MREs) are a type of intelligent material that can be actively controlled. However, the ferromagnetic particles in MREs are large, meaning that MREs contain many holes, which degrade the mechanical properties and fatigue resistance of MREs. In this work, liquid nitrile butadiene rubber-phenolic resin microcapsules were added as a self-healing agent to an MRE. The microcapsules reduced the number of holes caused by ferromagnetic particles and improved the mechanical properties and fatigue resistance of MREs. The magnetorheological effect of the MRE was not affected and was similar to that of the MRE without the self-healing agent. Under 100% strain and with the same number of cycles, the crack growth rate of the MRE without the self-healing agent was approximately 236% faster than that of the corresponding MRE with the self-healing agent and the crack length was approximately 136% longer.