PCM of nickel and its alloys and the measurement of nickel ion concentration in ferric chloride etchant

PCM of nickel and its alloys and the measurement of nickel ion concentration in ferric chloride etchant

Abstract: This paper reviews the nickel and nickel alloy products manufactured by PCM using etchants based on aqueous ferric chloride solutions. The metals include varying percentages of nickel that build up in the etchant as the metal is dissolved. It has been shown that, above a certain concentration, the presence of nickel ion affects etched edge acuity and the surface finish of the half-etch adversely and therefore it is necessary to be able to quantify the concentration of the nickel ion build-up in the ferric chloride. This may be done on-line using spectrometric analysis and examples of the methodology are illustrated.