Abstract
Extensive researches in the past on methods of producing metallic powder by atomizing the molten metals with air or water jets have resulted in the industrialization of a number of these methods. However, no intensive research has yet been accomplished on the centrifugal method of atomizing the molten metals by revolving a rotor at an enormous speed, although the principle had been generally known. The research under discussion undertakes to probe the atomizing effects involved in the centrifugal atomizing process and thereby to bare the basic technicalities involved in the process. Many problems yet need to be solved before this process can be industrialized, but it has been confirmed that this process is highly promising for industrialization.
The principal dimensions of the rotor used in this experiment were as follows : outermost periphery of rotor 65mm, conical angle of inner surface 70°and maximum speed of rotor 20, 000 rpm. The nozzles on the underside of the melting pot were given five diameters of 0.8mm, 1.0mm, 1.2mm, 1.4mm and 1.6mm.
The predominant results obtained in the experiment are as follows :
(1) Distribution of the particle size is adjustable freely by changing the number of revolutions.
(2) The grain diameter of the metallic powder obtained is considerably uniform as compared with that prepared, by the method of utilizing gas ; that is, the distribution of particle size makes a sharp curve.
(3) Since no gaseous matter is employed in the atomizing process, the recovery of the obtained powder is very easily done.
