Magnetostrictive energy conversion ability of Iron Cobalt Vanadium alloy sheet: Experimental and theoretical evaluation

The increasing demand for autonomous devices has made the concept of energy harvesting a significant industrial and academic point of interest. In this domain, an ideal magnetostrictive material for converting mechanical vibrations into electrical energy in a cost-effective way (i.e. competing with the price of primary batteries) remains to be determined. Iron-Cobalt-Vanadium (Permendur, Co49-Fe49-V2) is a promising candidate: it is a soft ferromagnetic material with high magnetization saturation, high magnetostrictive coefficients, low price, and good availability.In this study, the experimental magnetic characterization and simulation of Permendur sheets under tensile stress were performed, and their energy conversion capabilities were assessed. The conversion ability was predicted using thermodynamic Ericsson cycles from reconstructed anhysteretic curves. A maximum of 10.45 mJ cm-3 energy density was obtained under a tensile stress of 480 MPa and a magnetic excitation of 5.5 kA m-1. Then, an additional estimation was proposed to account for the hysteresis losses. For this, major hysteresis loops at different stress levels were considered, yielding an energy density of 3.52 mJ cm-3. Finally, experimental Ericsson cycles were performed to prove the feasibility of the conversion and corroborate the energy level predictions.