2023 年 72 巻 10 号 p. 729-736
There is a method using a strain gauge as a dynamic measurement of micro-fatigue cracks. However, it is not always effective in term of measuring micro-fatigue cracks due to direct adhesion with the object and durability issues. Therefore, we focused on the inverse magnetostrictive effect, which is a magnetic effect of ferromagnetic materials, and measured the change of the magnetic field by a simple instrument without adhesion with glue. It is possible to measure micro fatigue crack information.In this study, the change of magnetic field around specimens caused by the inverse magnetostrictive effect was obtained and analyzed using a coil and a hall sensor. Based on a certain coil output, the coil output was estimated from the relationship between the strain rate and the coil output.