Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : December 22, 2018 - December 24, 2018
Energy harvesting devices from ambient energy (e.g. shock, vibration, thermal energy) have drawn a lot of attentions due to Internet of Things (IoT). The IoT comprises everyday objects, lightness, stiffness and energy conversion efficiency are required for the devices. In this study, we fabricated as-drawn or annealed magnetostrictive FeCo wires dispersed epoxy resin matrix (FeCow/Epoxy) composites and investigated their output voltage density by compression tests. The compression tests were carried out using five cyclic programs with some constant velocities. In addition, the output voltages were predicted by simple nonlinear magnetomechanical coupling model of the FeCow/Epoxy composites. The measured output voltage densities of FeCow/Epoxy composite with tensile residual stress was consistent with the predicted values. It seems that our model is available to design novel magnetostrictive wire/polymer composites and predict their capability as a sensor and an energy harvester. Moreover, the output voltage density of annealed FeCow/Epoxy composite was larger than that of as-drawn one. This result clearly showed that the inverse magnetostrictive characteristics of FeCo wire was improved by the heat treatment. In addition, the magnetostrictive composite design utilizing the characteristics of FeCo wires enable to develop energy harvesting devices. This study indicates that FeCo is expected to be use in sensors and actuators in severe environment because it can withstand high pressure and temperature.
