Stress sensor performance of sputtered Fe-Si-B alloy thin coating under tensile and bending loads

This study evaluated the stress sensing performance of a thin coating of Fe-Si-B alloy. Particularly, a sputtered Fe-Si-B alloy thin coating with a thickness of 1500 nm on a polyimide substrate and a sputtered Fe-Si-B alloy thin coating with a thickness of 500 nm on a silicon wafer substrate were prepared for tensile and bending tests, respectively. The inductance of the Fe-Si-B alloy thin coating significantly decreased with slight changes in both tensile and bending stresses. Furthermore, the external magnetic field effectively improved the sensitivity of the target load region. Consequently, Fe-Si-B alloy thin coating can be applied as micro force sensors. [Display omitted] •The inductance of the Fe-Si-B alloy thin coating inversely decreased with tensile loading until 1.5 N.•The inductance of the Fe-Si-B alloy thin coating significantly decreased with a slight positive and negative load.•The Fe-Si-B alloy thin coating can detect slight tensile stress changes.