Process for conditioning the copper or copper-alloy external surface of an element of a mold for the continuous casting of metals, of the type including a nickel plating step and a nickel removal step
US5788824A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Apr 11, 1997 |
| Grant date | Aug 4, 1998 |
| Priority date | — |
| Expiry date | Apr 11, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25D5/34
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The subject of the invention is a process for conditioning the copper or copper-alloy external surface of an element of a mold for the continuous casting of metals, of the type including a step of nickel plating of said surface and a step of nickel removal therefrom, wherein: a preparation of said surface, comprising in succession an operation of cleaning said bare surface, an operation of pickling said bare surface in an oxidizing acid medium and an operation of brightening said bare surface, is carried out; then, an operation of nickel plating of said bare surface is carried out by electroplating, by placing said element as the cathode in an electrolyte consisting of an aqueous nickel sulfamate solution containing from 60 to 100 g/l of nickel; then, after said element has been used, an operation of partially or completely removing the nickel from said surface electrolytically is carried out, by placing said element as the anode in an electrolyte consisting of an aqueous nickel sulfamate solution containing from 60 to 100 g/l of nickel and sulfamic acid in an amount from 20 to 80 g/l, and the pH of which is less than or equal to 2; and then a new nickel plating of said surface is …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.