Abstract
The paper presents the influence of the ultrasounds surface effect up the drawing force and up the mechanical
characteristics of resistance and plasticity, at the processing of the thin walls tubes made of X5CrNi18-10 / EN 1008-3 /
2005, in ultrasound field / UVD system. The drawing force is measured with the drawing cell, a CT-A-KN1C one, (during the
process of plastic deformation by drawing) and the mechanical characteristics of resistance and plasticity are determined by
tension stress on samples made of classic processed tube (CT) and of ultrasonic processed tube (UVD) – accordingly with
EN 10002-2-1995. The ultrasounds surface effect or the effect of the metal-tool contact friction reduction / Severdenko’s
model, is explained based on the mechanism of the mean friction reversal at the level of one complete time of the oscillation
(T), assuming a Coulomb type friction. As a reduction measure of the friction at the metal-tool contact is the reduction
coefficient of the mean friction (φ) – as a function of the relative rate of drawing ( vdr / vv ), where dr v is the rate of drawing
and v v is the vibratory rate of the die. The results important to be considered are for dr v v / v << 1.0..
Keywords
Ultrasounds surface effect, Reduction coefficient of the mean friction, Thin walls tubes made of stainless steel, Drawing
force, Mechanical characteristics of resistance and plasticity.
Citation
E. CHIRILĂ, M. SUSAN, B. – L. GAVRILĂ, V. BULANCEA, Influence of the ultrasounds surface effect at the ultrasonic drawing of the thin walls tubes made of stainless steel, Optoelectronics and Advanced Materials - Rapid Communications, 8, 11-12, November-December 2014, pp.1129-1134 (2014).
Submitted at: Jan. 29, 2014
Accepted at: Nov. 13, 2014