C. Vives, CRYSTALLIZATION OF ALUMINUM-ALLOYS IN THE PRESENCE OF CAVITATION PHENOMENA INDUCED BY A VIBRATING ELECTROMAGNETIC PRESSURE, Journal of crystal growth, 158(1-2), 1996, pp. 118-127
A new magnetohydrodynamic method of transmitting forced vibrations to
solidifying aluminum alloy melts has been developed. Contrary to the c
ase of the conventional mechanoacoustic systems, this device lends its
elf very well to a fundamental investigation. The relatively accurate
knowledge of both the electromagnetic pressure and the local velocity
peaks has enabled us to reveal the specific effects of the oscillatory
flow and of the cavitation phenomena on grain refinement. It has been
shown that the cavitation threshold depends both on the surface state
of the crucible internal walls and on the electromagnetic pressure pe
ak. In the presence of well-developed cavitation situations, a very fi
ne and homogeneous microstructure has been observed throughout the ing
ots.