Numerical simulation and experimental research of low voltage pulsed magnetic field DC casting of AZ80 magnesium alloy

被引：0
|
作者：
Ji H.-M. [1 ]
Luo T.-J. [1 ]
Yang Y.-S. [1 ]
机构：
[1] Institute of Metal Research, Chinese Academy of Sciences, Shenyang
来源：
Zhongguo Youse Jinshu Xuebao/Chinese Journal of Nonferrous Metals | 2017年 / 27卷 / 03期
关键词：
Direct chill casting; Grain refinement; Low voltage pulsed magnetic field; Magnesium alloy; Numerical simulation;
D O I：
10.19476/j.ysxb.1004.0609.2017.03.004
中图分类号：
学科分类号：
摘要：
The electromagnetic field, flow field and temperature field during the low voltage pulsed magnetic field direct chill casting of AZ80 magnesium alloy were simulated with finite element method, and the microstructure of the billet was observed by comparing those of billet by conventional direct chill (DC) casting process. The simulation results indicate that, during the low voltage pulsed magnetic field DC casting process, affected by electromagnetic force, forced convection and velocity vibration generate in the melt, leading to the reduced temperature grade of melt along the radial direction. The results show that the grains of the billet cast with low voltage pulsed magnetic are significantly refined and the tip of dendrite is rounded, compared with those of the conventional one. During the low voltage pulsed magnetic field DC casting process, the critical nucleation radius and critical nucleation energy near the crystallizer decrease, at the same time, the nuclei formed ahead the inner wall of crystallizer can be dispersed into the centre of the molten pool with the convection that caused by the pulsed magnetic field, which causes the increased nucleation rate. In addition, the growth of dendrite tip is inhibited by the passivation effect of the pulsed magnetic field, which leads to the grain refinement in the low voltage pulsed magnetic field direct chill casting billet. © 2017, Science Press. All right reserved.
引用
收藏
页码：468 / 476
页数：8
相关论文
共 26 条
  • [1] Shepelev D., Klempf J., Bamberger M., Katsman A., Grain refinement and mechanical properties enhancement of AZ91E alloy by addition of ceramic particles, Journal of Materials Science, 46, 17, pp. 5798-5806, (2011)
  • [2] Caceres C.H., Mann G.E., Griffiths J.R., Grain size hardening in Mg and Mg-Zn solid solutions, Metallurgical and Materials Transactions A, 42, 7, pp. 1950-1959, (2011)
  • [3] Yu Y.-D., Zhang L., Li C.-X., Effects of electromagnetic stirring on microstructure and properties of Mg-Zn-Ca-Zr alloy before and after equal channel angular pressing, The Chinese Journal of Nonferrous Metals, 24, 6, pp. 1422-1427, (2014)
  • [4] Wang L., Kim Y.M., Lee J., You B.S., Improvement in rollability of AZ91 magnesium alloy by carbon addition, Materials Science and Engineering A, 528, 3, pp. 943-949, (2011)
  • [5] Barnett M.R., Beer A.G., Atwell D., Oudin A., Influence of grain size on hot working stresses and microstructures in Mg-3Al-1Zn, Scripta Materialia, 51, 1, pp. 19-24, (2004)
  • [6] Guo S.-J., Cui J.-Z., Le Q.-C., Zhao Z.-H., The effect of alternating magnetic field on the process of semi-continuous casting for AZ91 billets, Materials Letters, 59, 14, pp. 1841-1844, (2005)
  • [7] Zhang Z.-Q., Le Q.-C., Bao L., Cui J.-Z., Effects of low frequency electromagnetic field on surface quality, microstructure and hot-tearing tendency of semi-continuous casting ZK60 magnesium alloy billets, China Foundry, 10, 6, pp. 351-354, (2013)
  • [8] Guo S.-J., Le Q.-C., Zhao Z.-H., Wang Z.-J., Cui J.-Z., Microstructural refinement of DC cast AZ80 Mg billets by low frequency electromagnetic vibration, Materials Science and Engineering A, 404, 1, pp. 323-329, (2005)
  • [9] Guo S.-J., Le Q.-C., Han Y., Zhao Z.-H., Cui J.-Z., The effect of the electromagnetic vabration on the microstructure, segregation, and mechanical properties of as-cast AZ80 magnesium alloy billet, Metallurgical and Materials Transactions A, 37, 12, pp. 3715-3724, (2006)
  • [10] Zhang Z.-Q., Le Q.-C., Cui J.-Z., Structure and mechanical properties of AZ31 magnesium alloy billets by different hot-top semi-continuous casting technology, Rare Metals, 30, 4, pp. 414-418, (2011)
123