Electroplastic effect in metals

Abstract

A mechanism of electroplastic effect considered as well as possible areas of its technological application during rolling, drawing, stamping of thin sheets and other methods of metals forming.A conception justified that metal electroplastic deformation, based on electroplastic effect, can be applied at middle and final metallurgical stage. Electroplastic effect allows to decrease metal resistance to deformation by 25–30% and increase the ductility of a metal during its forming, to increase residual ductility till 30%. Due to increasing of axial texture perfection degree of wire during drawing technology with electroplastic effect application, a decrease of its electric resistance by 15% is reached. During the metal electroplastic deformation of stainless steels the austenite-martensitic phase γ→α transformation is practically completely suppressed, which makes unnecessary operations of money-and energy consuming austenizating annealing.Based on electroplastic effect about 45 mills and powerful metal-processing facilities, using metal electroplastic effect deformation created in different countries (mainly in Russia, South Korea, Italy, Great Britain and China). Different variants of effective energy-saving critical technologies are being developed by metal electroplastic effect deformation by rolling, drawing, stamping and flatting, as well as briquetting of metal wastes with current. A new equipment is created and existing equipment is modernized for application of metal еlectroplastic effect deformation technology.

Investigation of the electroplastic effect using nanoindentation

“…Similarly, Okazaki et al [10] and Troitskii [43], have reported larger stress drops with increasing current density. In the present study, an increase in current intensity is interpreted as increased current density at a constant pulse length.…”

“…The high stress drop induced by the first electric current pulse observed in the current study might be caused by the electron wind effect [1,5,11,12], which is assumed to help dislocations to overcome obstacles. We therefore assume that during the first current pulse dislocations present in the microstructure are de-pinned from short-range obstacles, hence, inducing a major stress drop.…”

“…Early work by Troitskii et al [1,11] and later by Conrad et al [5,12] considered the effect of the 'electron wind', i.e. the drift of conduction electrons upon application of an electric potential, in assisting dislocations to overcome lattice obstacles.…”

Effect of Electromagnetic Treatment on Fatigue Resistance of 2011 Aluminum Alloy

“…The study of the effect of the electromagnetic field (EMF) treatment on the resistance to fatigue damage in sheet metals hasn't received much attention by the fatigue research community, but has nevertheless been in discussion for many years. For example, an increase of the fatigue life of lowcarbon steel following pulsed magnetic field pre-treatment was reported in [1]. An increase of more than 50% in fatigue limit was reported for stainless steel after a pulsed electric current pre-treatment [2].…”

A study on electric pulse treatment of stainless steel constructive forming process

“…Xie et al [3] studied the hot compression bonding experiment of 316LN stainless steel, and analyzed the healing mechanism and mechanical properties of metal bonding interface under different IOP Publishing doi:10.1088/1757-899X/1270/1/012027 2 deformations and holding conditions. Troitskii and Likhtman found that the forming properties of metal materials changed significantly and the plasticity was improved to a certain extent after loading current, and this phenomenon was called the electroplastic effect [4,5]. Okazaki et al found that the electroplastic effect could be observed even if the temperature of the material surface was low.…”