Abstract: High purity metallic powder is made from high purity metallic rod by positioning the rod above a horizontally oriented, cooled and rotating electrode. An electric potential is applied between the rod and the electrode so that the electrode end porixmate the disc is progressively melted down. Molten droplets are thrown off the disc by centrifugal forces onto a cooled, rotating, concave shield which intercepts the trajectory of the droplets. As the droplets contact the cooled shield they solidify and are deflected into a collector. The melting and cooling operations are performed in a controlled atmosphere, e.g., in a vacuum.

Abstract: Apparatus and a method for cutting a workpiece by a rotary arc saw wherein the residue from the cutting of the workpiece presents atmospheric contamination or the like. The apparatus includes a cutting chamber adapted to contain a fluid coolant which is flowable into and out of the chamber continuously. A rotary arc saw is mounted in the chamber in spaced relationship to a workpiece mount so that, when an arc is established between the arc saw and the workpiece, the workpiece will be progressively cut by the heat of the arc until it is cut to a predetermined depth or is completely severed. An impeller is carried by the arc saw for rotation therewith. The impeller extends below the upper level of the fluid coolant therein and causes circulation of the fluid in the chamber to present a fluid curtain which extends upwardly and across the fluid outlet of the chamber. The residue from the cutting action is caused to circulate in the curtain and to pass out of the chamber to the fluid outlet thereof.