Table of Contents Author Guidelines Submit a Manuscript
Advances in Materials Science and Engineering
Volume 2014, Article ID 240879, 8 pages
http://dx.doi.org/10.1155/2014/240879
Research Article

Effects of Electric Pulse Current on the Aging Kinetics of 2219 Aluminum Alloy

1State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, China
2School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China

Received 4 June 2014; Revised 12 August 2014; Accepted 22 August 2014; Published 2 September 2014

Academic Editor: Liyuan Sheng

Copyright © 2014 Jiao Zhang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The conventional aging experiments and the low density electric pulse current (LDEPC for short) added aging experiments, with the self-made positive and negative alternating pulse power equipment, were conducted to study the influence of LDEPC on the dynamics of phase transformation in 2219 aluminum alloy by means of measuring the variation of hardness with aging time. The results showed that the hardness in both aging systems increased with the increasing of aging time until it reached the peak value; then it gradually reduced. The hardness of LDEPC added aging is generally greater than the conventional one before the peak aging time. The Avrami dynamics equation of conventional isothermal aging was obtained based on the hardness evolution law. The effects of electromigration and ponderomotive force were introduced into the Avrami empirical equation; in turn, the dynamics equation of LDEPC added aging was established. At last, the isothermal transformation curves of both the regular aging and the LDEPC added aging were derived which revealed that the nucleation rate, as well as the growth rate, was promoted by electric pulse current. The research work provided the theoretical support for the regulation of the coupling energy field on the dynamics of phase transformation in 2219 aluminum alloy.