简介: |
Abstract
Liquid metal processing by using a strong magnetic field has been a topical research field, especially, in the processing of solid particles manipulation and related metallic based materials preparation. In the present work, hypereutectic Al-Cu alloys with 50 wt% Cu and 35 wt% Cu are processed by using a strong magnetic field up to 12 T. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and electron backscattered diffraction (EBSD) are applied to investigate the strong magnetic field effects on the microstructure, especially on the Al2Cu phase precipitation behavior. After a strong magnetic field treatment, weak magnetic Al2Cu crystals are aligned forming pseudo-single crystals when the Cu content is high and forming chains when the Cu content is lower. It is realized that three phenomena are active in parallel after the primary Al2Cu phase reaches a critical size: magnetic alignment, magnetic dipole-dipole interaction and crystal rotation. Subsequently, the magnetic alignment is quantitatively evaluated by using the Lotgering factor and it is noticed that both morphological and crystallographic alignment are obtained. Crystallographically, the paramagnetic Al2Cu crystal is easy to be aligned (e.g. in a 1 T field) and c-axis is found to be parallel to the magnetic field. However, the magnetic field density needs to be high enough to reach an obvious morphological alignment. Additionally, mechanical property of the Al2Cu phase is checked and the toughness of a pseudo-single crystal along the magnetic field direction is found to be significantly improved according to Vickers micro-hardness tests.
CV:
Zhi Sun (孙峙)
Department of Metallurgy and Materials Engineering, Katholieke Universiteit Leuven
Kasteelpark Arenberg 44, BE-3001 Heverlee (Leuven), Belgium
Education:
- Bachelor Degree of Engineering, University of Science and Technology, Beijing (USTB), 2000-2004
- Master Degree of Engineering, Chinese Academy of Sciences (CAS), 2004-2007
- Doctoral Degree of Engineering, Katholieke Universiteit Leuven, 2007-current (viva on 24th October 2011)
Research experiences:
2007 – now
- Strong magnetic field processing of materials – Electromagnetic metallurgy and materials engineering
- Lime dissolution behavior in CaO-Al2O3-SiO2 based slags – Pyrometallurgy
2004 – 2007
- Optimisation of the oxidative leaching process of chromite ore with caustic alkali and investigation of the mechanism of the process – Hydrometallurgy
- Chromium extraction from a waste water from phosphorite hydrometallurgy
- Comprehensive utilization of red mud from an alumina plant in He’nan, China
- Comprehensive utilization of chromium containing residue in the cleaner production of chromates
Teaching experience:
- Teaching assistant of P&O materials life cycles 2009
- Teaching assistant of Winning and recycling of E-scrap 2010
- Supervisor of master thesis of Liubin Yang 2009-2010
Awards and honors:
- CV selected by “Who’s Who in Science and Engineering 2011-2012”
- Chinese Government Award for outstanding self-financed students abroad, 2010 (Metallurgical engineering) – 国家自费留学生奖学金
- Excellent Graduate Award, Chinese Academy of Sciences, 2007 (2/70)
- Liu Yongling scholarship Award, Chinese Academy of Sciences, 2007 (1/70)
- Excellent Graduate Award of Beijing, China by National Educational Committee, 2004 (5/119)
- Outstanding Undergraduate Student of Beijing, China, 2003 (1/119)
- Silver and Bronze prize in the 2th Beijing in the 8th China “Tiao Zhan Bei” Academy and Science Article Competition, 2003 (1/119)
Visiting research:
- Visiting research in the group of Prof. Zhongming Ren, Shanghai University, 2009.11~2010.2
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