barreau métallique

CONT: Fusion de zone, méthode ultime de purification des métaux, qui consiste à déplacer une petite zone fondue le long d'un barreau métallique dans le but de repousser aux extrémités de celui-ci les différentes impuretés qu'il contient.

CONT: Zone melting. The term applied to a method of separation by fusion (and hence of purification) in which one, or a series, of molten zones traverses a bar or rod of metal. The molten zone as it progresses through the bar melts impure solid at the forward edge (the impure melt has a lower melting point than the pure metal) and leaves purer metal solidified behind the rear edge. Thus the impurities tend to concentrate in the melt and move towards one end of the bar.