STUDY OF DEFORMATION AND CONTACT HEATING OF WIRE DURING THE HIGH-SPEED DRAWING PROCESS IN A MONOLITHIC DIE

Abstract

This article presents the results of analytical studies of the deformation and contact heating of the wire, depending on the drawing technological parameters. The analysis was carried out by the calculation method and the computer simulation method in the QForm package based on the finite element method. The increase in the temperature of the wire during drawing in a monolithic die consists of deformational heating and heating caused by sliding friction on the “wire – die” surface. In the course of the research, it was found that the half-angle of the die has an effect on the uniformity of the distribution of deformation and, as a consequence, on the deformation heating over the wire section. With an increase in the die half-angle in the surface layers, the metal heats up to higher temperatures than in the central section. The values of deformation heating obtained by calculation are consistent with the results obtained in a numerical experiment. The deformation heating in both cases does not exceed 50 °C. An increase in the drawing speed from 10 to 40 m/s leads to an increase in deformation heating by 2–4 °C. Heating of the wire due to contact sliding friction, depending on the technological parameters of drawing, can reach 300 °C. An analysis of the temperature field during wire heating due to sliding friction in computer simulation showed that the proportion of metal heated to a temperature above 150 °C does not exceed 5%. About 50% of the metal volume is heated only due to deformation, and 45% of the metal volume is heated to temperatures of 70–150 °C due to deformation and heat conduction from the surface layer heated due to sliding friction. A comparative analysis of the calculated values and the results of computer simulation showed that both methods show similar results. The advantage of computer simulation is the ability to estimate the temperature field over the wire section, and the advantage of the calculation method is the high speed of obtaining information in the evaluation calculations.