METHOD OF TREATING OUTER SURFACES OF CONTINUOUS CASTING MOULD COMPONENTS MADE OF COPPER OR ITS ALLOYS, INCLUDING NICKEL PLATING STAGE AND STAGE OF REMOVING THE NICKEL COATING FROM THAT SURFACE

• Main Authors: RAISSON GERARD, ALLELY CHRISTIAN, CATONNE JEAN-CLAUDE, NICOLLE REMY
• Format: Patent
• Language: English
• Published: 13.10.1997
• Edition: 6
• Subjects: APPARATUS THEREFOR; CASTING; CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; ELECTROFORMING; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLICMATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASSC23 AND AT LEAST ONEPROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25; NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; PERFORMING OPERATIONS; POWDER METALLURGY; PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTIONOF COATINGS; PROCESSES FOR THE ELECTROLYTIC REMOVAL OF MATERIALS FROMOBJECTS; TRANSPORTING

The external surface of a copper or copper alloy mould, which may comprise one or two rollers and is used for continuous casting of metal, is degreased, pickled in acid, polished and electrolytically coated with nickel, using an aqueous electrolyte solution of nickel sulphamate containing 60-100 gms. of nickel per litre with the mould acting as cathode. The mould is then used for a period, after which the coating is partly or wholly removed electrolytically, the mould acting as anode in an electrolyte comprising the same amount of nickel sulphamate plus 20-80 gms/litre of sulphamic acid giving it a pH of up to 2, and then a new nickel coating is applied.