We study how the shape of parts obtained through the LASER cladding process can be controlled by application of an ac magnetic field by means of two simple physical models: a numerical and an experimental one. More specifically, we show that straight metallic joints of high aspect ratio can be obtained by using inductors of triangular cross-section that concentrate electromagnetic forces at the bottom of the joint. The effect is first demonstrated on a numerical model for an infinitely long joint such as: we illustrate how the joint shape can be controlled by varying the inclination of the inductor and for a magnetic Bond number Bom = 60 (which measures the ratio of electromagnetic to capillary forces), we obtain a joint of aspect ratio up to 7.2. We further find that inductor angles in the range 15°–25° lead to joint side faces that are close to vertical. These findings are then verified experimentally by placing a liquid metal drop in a purpose built inductor of triangular cross-section. We find a good agreement between the theoretical prediction of our two-dimensional model and the real three-dimensional drop. For the highest magnetic Bond number our generator could deliver, Bom = 20.19, we achieved a drop aspect ratio of 2.73.
Bibliographical noteCopyright (2010) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Andreev, O. , Potherat, A. and Thess, A. (2010) Generation of liquid metal structures of high aspect ratio by application of an ac magnetic field. Journal of Applied Physics, volume 107 (12): 124903 and may be found at http://dx.doi.org/10.1063/1.3409075.
- joining materials
- laser materials processing
- liquid metals
- numerical analysis