Preparation of metallic and intermetallic powders by spark erosion
A spark erosion technique for the preparation of finely divided metallic and intermetallic powders is described. An X-ray diffraction line-broadening analysis was used to compare the average particle size obtained for a spark-produced nickel powder with that of a commercially prepared catalyst, Raney nickel. The average particle size of the Raney nickel powder was found to be approximately 6 nm smaller than that obtained from nickel powder sparked at an electrode potential of 700 V and a discharge energy of 3.92 J. Although certain intermetallic compounds could be prepared as powder blacks using the spark erosion method, traces of one of the individual elemental components were usually found in the powder. It appears that, in general, many materials may be produced as powders by a spark erosion technique provided they are electrically conductive.
