Method for heating aluminum baths

Abstract

Aluminum electroplating installations containing aprotic electrolyte bath systems typically require an electrolyte operating temperature of over 80.degree. C. in order to achieve useable aluminum precipitations. The warming-up and heating of such aluminum electrolyte baths has heretofore been accomplished with indirect heating methods, such as surrounding the baths with a heating jacket or by conducting electrolyte out of the bath through a heat exchanger and then returning the heated electrolyte. The present invention concerns a more efficient heating method whereby Joule's heat is used to heat an aprotic electrolyte bath. Accordingly, at least two electrodes are immersed into the electrolyte and charged with alternating pulses by a square wave pulse generator such that a heating current flows through the electrolyte. The anodes and cathodes of the aluminization electrolyte bath are preferably used as the heating electrodes.

Dependencies are inferred from the claim text.