Investigation of the workability and surface roughness of thin brass wires in various dieless drawing technologies

Abstract

Possibilities of improving the workability of the CuZn37 brass thin wire in a diameter of 0.14–0.18 mm produced by the dieless drawing processes were explored. The workability was defined as the maximum final longitudinal strain of the wire up to its fracture, achievable in the dieless drawing process. Two technologies of dieless drawing were developed and their workability was compared. The first one is the classical one-pass process; the second, a multi-pass one. For both developed technologies, it was possible to obtain a good-quality product but more than two times higher workability has been demonstrated for the multi-pass technology. No evident effect of the deformation temperature from the window of technologically accepted parameters on the workability was found but an increase in the temperature significantly increased the roughness of the product surface. For the same deformation temperature, the roughness of the wire obtained from the multi-pass process appeared to be significantly lower than for the one of the classical one-pass technologies.

Achieving thin wall and high surface quality of magnesium alloy tubes in combined process of hollow sinking after die-less mandrel drawing

“…The aim of this study is to achieve a thin wall and low surface roughness in the fabrication process of Mg alloy tubes. Although die-less mandrel drawing is suitable for fabricating thin-walled microtubes, it often increases the outer surface roughness [24,25]. Kishimoto et al reported that the slip deformation of the pyramidal slip system was mainly responsible for the roughening of the outer surface in die-less mandrel drawing [26].…”