Throwing Index A New Graphical Method for Expressing Results of Throwing-Power Measurements

Abstract

A new direct method is proposed for expressing the results of throwing‐ power measurements made on plating solutions in a conventional rectangular throwing‐power box with plane parallel electrodes. The metal distribution ratio (M) is plotted vs. the linear ratio (P) on arithmetic coordinates. The reciprocal of the slope of this plot is called "Throwing Index" and represents a direct measure of bath throwing‐power. Experimental data on several solutions are presented and advantages of this method are discussed.