HYDROGEN EMBRITTLEMENT OF COLD DRAWN PRESTRESSING STEELS: THE ROLE OF THE DIE INLET ANGLE

摘要

Cold-drawn prestressing steel wires are susceptible to hydrogen embrittlement (HE) in aggressive environments, and the residual stress-strain states generated in wires by the drawing process play the key role there. Hence, the alterations of the stress-strain fields due to the specific features of the drawing procedure affect the serviceability of wires under HE. On the basis of performed numerical simulations of the process of cold drawing with the use of different drawing dies, the paper addresses the effect of the inlet angle of the die on the residual stress-strain fields in the wires. We also deduce their consequences for the hydrogenation of wires and their susceptibility to HE. The reduction of the die inlet angle is shown to be beneficial for the performance of wires.