Patent 7575623 was granted and assigned to Bayer on August, 2009 by the United States Patent and Trademark Office.
A method is described of treating aluminium-metal alloys with organic or inorganic bases by exposing them to an aqueous solution of the base, removing the aqueous base and washing the treated alloy material, the leaching process being monitored, during the time of exposure to the base, on the basis of the potential which is established at a measuring electrode as a result of the treated aluminium-metal alloy and the hydrogen which may be formed during the reaction.