Mechanism of the Electrochemical Deposition of a CoNiFe Alloy

Abstract

Heating the chloride electrolyte to a temperature of 70°C ensures the normal codeposition of the components of the CoNiFe alloy as a result of the discharge of single-charged iron and cobalt species (Fe2+Cl-)+ and (Co2+Cl-)+, respectively and double-charged Ni2+ ions at a high cathode current density. The chloride electrolyte obtained with filtration and pH correction by hydrochloric acid provides the electrochemical deposition of CoNiFe films with a CCo:CNi:CFe ratio of 1:1:1. The mechanism of the abnormal deposition of Co, Fe and Ni occurs due to the incomplete ionization of atoms and differences in ion mobility. Based on the experimental results of CoNiFe films, an electrochemical deposition mechanism is proposed. In contrast to the well-known in the literature, the phenomena occurring in the volume of electrolyte, including transmission of ions, with the determining effect is the mobility and formation of positive ions on the anode. CoNiFe films are produced without mechanical stresses, with a uniform structure and with high magnetic parameters without a high burn temperature. Electrochemical deposition when the charge of ions in the electrolyte is taken into account allows to obtaining a reproducible electrochemical deposition of CoNiFe films.