Influences of Magnetic Properties of Beam Electroplated With 3d Ferromagnetic Transition Metal Film on the Output Characteristics in Magnetostrictive and Perpendicular Magnetic Field-Assisted Vibration Powered Generators

Cu base plates are electroplated with Fe100-xCox and Fe100-yNiy (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$x =0$ </tex-math></inline-formula>–95 and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$y =1$ </tex-math></inline-formula>–100 at.%) films of about <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$30~\mu $ </tex-math></inline-formula>m thickness. They are applied to beam materials in electromagnetic vibration powered generators with inverse magnetostrictive and perpendicular magnetic field-assisted types. The influences of magnetic properties of coated film on the output characteristic are investigated. The Fe100-xCox beams with around <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$x =30$ </tex-math></inline-formula>–55 show high saturation magnetizations of about 1.650 kemu/cm3, moderately low coercivities of less than 10 Oe, and large saturation magnetostrictions of more than <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$+ 30\times 10^{-6}$ </tex-math></inline-formula>. However, high output characteristics are not obtained in both types of generations. The reason is that the Fe100-xCox beams exhibit only less than 20% of their potentials due to that their magnetocrystalline anisotropies are not so low. On the other hand, very low coercivities of less than 1 Oe are recognized for the Fe100-yNiy beams with around <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$y =35$ </tex-math></inline-formula>–70. As a result, the Fe100-yNiy films show high output voltages of 5–7 V and powers of 0.5–1.1 mW, which correspond to more than 60% of their potentials. The present study has shown that low magnetocrystalline anisotropy is essential in enhancing the output characteristic for both types of generators.