An Experimental Evaluation on Change in Impedance of TRIP Steel Subjected to Plastic Deformation at Various Strain Rates

摘要

For automotive industries, weight of an automobile can be reduced if TRIP steel which has excellent mechanical properties dominated by strain-induced martensitic transformation (SIMT) can be applied to shock absorption members. However, strain rate sensitivity of TRIP steels has not been fully understood because a relationship between a strain rate and an amount of martensite produced by SIMT is still unclear. In previous studies, volume resistivity and impedance have been measured to obtain information on the amount of produced martensite, however, these studies have not been succeeded to clarify the relationship. Here, by focusing a property that martensite shows ferromagnetism, it is attempted that impedance of TRIP steel is measured at various strain rates during the deformation by using prototype coil and circuits.