Influence of Drawings Speed on Residual Stresses in Reinforcing Wire

Abstract

Aiming at improving the relaxation resistance, this study focuses on the influence of the reinforcing wire drawing speed on the values of residual stresses and the uniformity of mechanical properties over the wire cross section. The methods of the study were the measurement of micro-hardness over the wire cross section, the method of neutron diffraction, and the method of finite element modelling. After the wire drawing speed rose from 4 to 6.3 m/s, the heterogeneity of the strength properties over the wire cross section increased while the average micro-hardness over the wire cross section either increased, or decreased depending on the steel grade of the wire. The neutron diffraction found an increase in the lattice parameter and in the values of residual stresses at the wire drawing speed 6.3 m/s. According to the results of finite element modelling, residual stresses were increasing, following the experimental data, until the speed reached 8 m/s, and then began to decrease. In most cases, residual stresses in the reinforcing wire increase as the drawing speed rises, but the opposite phenomenon is possible for some steel grades and temperature conditions. The results of the study can be used when developing the drawing modes for reinforcing wire.