Coherent Coatings of Refractory Metal

Abstract

A general process has been developed for the electrodeposition of eight of the nine refractory metals of groups IVB, VB, and VIB as dense coherent deposits. It consists essentially of the electrolysis of a solution of the refractory metal fluoride in a molten alkali-fluoride euteotic mixture, and has been shown to deposit a coating, unalloyed with the substrate, by a pro- cess that obeys Faraday's law. Some evidence exists that the electrode-reaction mechanism by which coherent coatings are deposited from molten salts incorporates an irreversible metalproducing step.