Patent ID: 6988529
Filing Date: 2006-01-24
Classification: B22D,C22C

Abstract:
1. A method for preparing a metal or metal-alloy product for a casting process wherein the product is manipulate-able in a semi-solidified state and in which crystallization nuclei are distributed uniformly therethrough, the product comprising a carrier material “melt” and an alloy, the method comprising the steps of: a) feeding the melt into a crystallization vessel, the melt having a temperature greater than a liquefaction temperature of the alloy, wherein the feeding step includes introducing the melt into the crystallization vessel in the form of a stream flowing between at least two electrodes positioned at an inlet of the crystallization vessel, the electrodes being at spaced intervals around the inlet and supplied with electrical power; b) introducing the alloy into the crystallization vessel simultaneously with the introduction of the melt, the alloy being in a pulverized form; c) mixing the melt and the alloy in the crystallization vessel by applying electrical and magnetic forces thereto by establishing an electrical current between an electrode integral to the crystallization vessel and an inlet of the crystallization vessel, thereby establishing an electrical arc between the melt and the electrode; d) maintaining the crystallization vessel at a temperature less than the liquefaction temperature of the alloy throughout the introduction and mixing steps; and (e) discharging the mixture of the alloy and the melt from the crystallization vessel in a semi-solidified state.