The Effect of Static Magnetic Field on the Channel Formation during Directional Solidification of Aqueous Ammonium Chloride Solution. Issue 9 (14th August 2018)

• Record Type: Journal Article
• Authors: Ding, Biao; Zhou, Tao; Ren, Weili; Zhong, Yunbo; Yu, Jianbo; Ren, Zhongming; Li, Fei
• Is Part Of: Crystal research and technology. Volume 53:Issue 9(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-08-14
• Subjects: convection -- directional solidification -- freckles -- magnetic fields -- magneto‐hydrodynamic effect; Crystallography -- Periodicals; 548
• DOI: 10.1002/crat.201800113
• Languages: English
• ISSNs: 0232-1300

Abstract

Abstract: This study investigates the effect of magnetic field on the channel formation by using a 27 wt.% aqueous ammonium chloride solution at an initial base temperature of 246 K (−27 °C) under magnetic fields of 0.03T, 0.05T, and 0.1T. The application of a magnetic field suppresses channel formation, as reflected by the delayed occurrence, the decreased number and density of channels, and the increased areas with no channels and mushy‐zone height necessary to form channels. The suppression of channel formation is caused by the magneto‐hydrodynamic (MHD) effect on convection during directional solidification. The higher temperature gradient in the mushy zone under an applied magnetic field further confirms the mechanism. The present investigation would help to provide useful predictions for the influence of magnetic field on channel formation during the directional solidification of alloys. Abstract : Effect of longitudinal static magnetic field on channel formation of a 27 wt% aqueous ammonium chloride solution during directional solidification is studied. The application of the magnetic field suppresses the channel formation, the decreased number and density of channels, and the increased no‐channel areas and mushy‐zone height necessary to form channels. Increased magnetic field strength intensifies these effects.