Effects of Heat Treatment and Cr Content on the Microstructures, Magnetostriction, and Energy Harvesting Performance of Cr‐Doped Fe–Co Alloys

Abstract

The novel coronavirus (COVID-19) has had a great impact worldwide, and various Internet of Things (IoT) systems have recently been used to combat COVID-19 infections. [1,2] Many such systems are already in operation around the world for this purpose because they are well suited to the automation of data analysis and the processing of information collected by sensors, so as to eliminate the need for human intervention as much as possible. As the usage of both the IoT and big data increase, the number of different sensors that are employed, including biosensors, is also expected to undergo an explosive increase. [3] Consequently, the powering of these sensors will become an important social and economic issue, and energy harvesting, which converts unused kinetic energy into electrical energy, has attracted attention in this regard.Piezoelectric ceramics, magnetostrictive alloys, and their composites have all been studied with the aim of improving the performance of the materials and devices applied to energy harvesting. [4][5][6] In particular, piezoelectric ceramics and composites have a wide range of applications, [7][8][9][10][11] although research concerning magnetostrictive materials has also been conducted. [12][13][14][15][16] Energy harvesting devices that use the magnetostrictive effect are currently being investigated; however, the majority of such studies are focused on Fe-Dy-Tb (Terfenol-D) and Fe-Ga (Galfenol) alloys. Terfenol-D alloys are expensive and have the disadvantage of brittleness, [17,18] while Galfenol alloys have drawbacks in terms of mass productivity and processing cost. In contrast, Fe-Co alloys exhibit inferior magnetostrictive characteristics but are inexpensive and readily processed into wires. Therefore, the research and development of Fe-Co alloys has become very important.Recently, Katabira et al. [19] fabricated magnetostrictive polymer composites in which Fe-Co fibers were woven into a polyester fabric, and examined the performance of these composites as sensors. Wang et al. [20] also produced random magnetostrictive Fe-Co short fiber/polymer composite sheets and investigated the piezomagnetic coefficients of these materials both numerically and experimentally. Yang et al. [21]

Analytical solution and optimal design for the output performance of Galfenol cantilever energy harvester considering electromechanical coupling effect

“…The existing green energy can be roughly divided into solar energy 1 , 2 , wind energy 3 , heat energy 4 and environmental vibration energy 5 , 6 . In the field of ambient vibrational energy harvesting, the common energy harvesting mechanisms include electrostatic 7 , 8 , electromagnetic 9 – 11 , piezoelectric 12 – 14 and magnetostrictive 15 , 16 . The electrical energy converted from the harvested ambient vibrational energy can be used to power self-powered devices, such as microelectromechanical devices, wireless sensor networks, embedded structural monitors and remote condition monitoring devices 17 – 19 .…”

Young’s modulus and ferroelectric property of BaTiO3 films formed by aerosol deposition in consideration of residual stress and film thickness

“…7,8) For instance, vibration energy harvesting converts ambient vibrations into electrical energy. [9][10][11][12] Using this method, it would be possible to generate electrical energy from minute vibrations caused by water droplets, vehicles, and sound. 13,14) Piezoelectric materials can convert mechanical energy into electrical energy and have the potential to drive sensors despite their small size.…”

Negative Magnetostrictive Paper Formed by Dispersing CoFe 2 O 4 Particles in Cellulose Nanofibers

“…Since that time, researchers have developed various magnetostrictive materials such as Tb-Dy-Fe alloys (Terfenol-D), Fe-Ga alloys (Galfenol), Fe-Co alloys, and CoFe 2 O 4 (cobalt ferrites) [14][15][16][17][18]. Magnetostrictive materials, composites, and devices are also attracting attention in the energy harvesting eld [19][20][21][22][23][24]. Terfenol-D and Galfenol are well-known giant magnetostrictive alloys showing huge magnetostriction at room temperature, but are brittle and expensive [1,16].…”