An Estimation of Stress-induced Martensitic Transformation in Fe-28Mn-6Si-5Cr Shape Memory Alloy by Measurement of Volume Resistivity During Impact Tensile Deformation

Abstract

Because Fe-based shape memory alloy (Fe-SMA), is attempted to be applied to many engineering fields under different working environment loaded at various strain rates, it is necessary to evaluate stress-induced martensitic transformation which can control such excellent performances, at various strain rate. In this study, tensile tests of Fe-28Mn-6Si-5Cr alloy, which is one of Fe-SMA, are conducted under impact deformation. During impact deformation, it is attempted to evaluate the stress-induced martensitic transformation by measuring the volume resistivity as well as temperature for increasing a reliability of the alloy. The volume resistivity and temperature in the Fe-SMA is estimated experimentally by using the past-established circuit based on the Kelvin double bridge with a higher precision and an extremely-thin thermocouple as well as a laser Doppler vibrometer during impact tensile tests.