Heat build-up and dynamic compressive behavior of anisotropic magnetorheological elastomer

Heat build-up and dynamic mechanical behavior of an anisotropic magnetorheological elastomer (MRE) under cyclic compressive loading for 120 min at different pre-strains, strain amplitudes, and frequencies have been studied. The anisotropic MRE was fabricated by aligning micro-sized carbonyl iron particles in silicone rubber using an external magnetic field. The self-heating temperatures measured on the surface and at the center of anisotropic MRE cylindrical specimens under cyclic compressive loading increased rapidly at an initial stage and then moved toward a steady stage. The difference between internal and surface temperatures was considerable for large amplitudes and frequencies. Besides, the temperatures increased with rising pre-strain, strain amplitude, and loading frequency. The self-heating temperatures boosted powerfully with increasing the pre-strain to 10% and thereafter increased slightly. The storage modulus of the anisotropic MRE varied slightly with time, while the loss modulus decreased considerably with rising time. Although the dynamic moduli of the anisotropic MRE reduced with the rise in the strain amplitude, they enhanced with raising the pre-strain. The gain in the temperatures resulted in a decrease in the loss modulus. The numerical simulation of frequency- and amplitude-dependent temperature of the anisotropic MRE was investigated based on the dissipated energy during cyclic loading. The amplitude-dependent dynamic compressive moduli of the anisotropic MRE were well simulated using the Kraus model.