Experimental Identification of the Degree of Deformation of a Wire Subjected to Bending

Abstract

This study provides experimental verification of analytical results on maximum strain max in elements fabricated by bending a stainless steel wire around a cylinder with given dimensions. The method of measuring the thermal electromotive force (TEMF) of a thermocouple formed by joining the deformed metal specimen to a copper (Cu) conductor showed an increase in the thermal electromotive force coefficient (TEMFC) during heating with increasing degree of plastic deformation. For known values of plastic deformation produced by straining X5CrNi1810 stainless steel wire specimens of 2.8 mm diameter, the TEMF was determined as a function of the extent of deformation of the thermocouple consisting of the deformed steel wire specimen and the copper conductor. Based on the correlation (calibration curve), it was shown that the relative strain of the element fabricated by bending the same wire (made of X5CrNi1810 stainless steel, 2.8 mm in diameter) around the cylinder of 10 mm diameter is 23.8 %.