OPTICAL AND X-RAY STUDIES OF METAL SURFACES ERODED BY HIGH-VOLTAGE OSCILLATORY SPARK DISCHARGES

An electronically controlled, high-voltage oscillatory spark source has been modified to deliver single oscillatory sparks, which may be terminated after one, two, three, four, or six complete current half cycles. This source can be tuned to give single half-cycle discharges of constant peak current and variable duration. Physical and chemical changes resulting from sampling a variety of alloys by sparks of varying numbers of half cycles have been studied by photomicrography and electron probe microanalysis. Physical effects of trains of sparks on polished electrode surfaces have been observed. The problem of preferential spark sampling of a volatile major element in an alloy has been quantitatively studied by electron probe microanalysis. © 1969, American Chemical Society. All rights reserved.