We observe an elastic percolation transition in the yield stress (τy) of cobalt-nanowire magnetorheological fluids, with a critical volume fraction of ferromagnetic particles (pc) that increases with the applied magnetic field (H). Unlike studies of static percolation phenomena, our observations reveal percolation in a dynamic, fluid-semisolid system. The elastic critical exponent (f) appears to be independent of H, having a value in the range of 1.0-1.2, near that seen in various two-dimensional networks. The superelastic exponent (c) decreases with increasing H and is smaller than that seen in typical networks.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)