Effect of a pulsed magnetic treatment on the dislocation substructure of a.pdf

Materials Science and Engineering A 398 (2005) 108–112 Effect of a pulsed magnetic treatment on the dislocation substructure of a commercial high strength steel Guoyi Tang ∗, Zhuohui Xu, Miao Tang, Xihua Chen, Huihua Zhou, Anli Lu Advanced Materials Institute, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, PR China Received 18 October 2004; received in revised form 1 March 2005; accepted 1 March 2005 Abstract The improvement of physical and mechanical properties of some hard-to-deform metals under influence of an external magnetic field has been investigated for the last 30 years. Until now the magnetic filed treatment technology has not been applied widely in the field of engineering. In this paper, deformed specimens of commercial high strength steel were treated by a pulsed magnetic field using a self-made pulse magnetic treatment equipment. It has shown that when the deformed specimens are subjected to a pulsed magnetic process, the residual stress in the specimens is reduced by about 15–35%, and the dislocation substructure is changed due to the motion of dislocations. The behavior might be attributed to the effects of thermal and athermal activation of dislocations and magnetic field induced strain (magnetostriction). © 2005 Elsevier B.V. All rights reserved. Keywords: Pulsed magnetic treatment; Dislocation substructure; High strength steel; Residual stress 1. Introduction can be enhanced, therefore tangles of dislocations are easily unpacked. As above effects, the stress relaxation, fatigue life Intensive investigations of the static magnetic field treat- and resistance to stress corrosion increase and accu