| 摘要 |
A protective copper coating on an article of zirconium or a zirconium-base alloy is removed by anodic dissolution in an aqueous bath containing copper and sulphate ions. Preferably the bath contains 50 to 200 g/l CuSo4 and 25 to 100 g/l H2SO4, at a temperature of 20 DEG to 30 DEG C, the electrolyzing voltage is 0.5 to 10v, the cathode is one or more wire or expanded metal grids, the cathode current density is 0.5 to 1 A/sq.dm., and the cathode-anode surface ratio is from 0.1 to 10. If the article is a tube or of re-entrant form a cathode may be inserted into the re-entrant space while if it is of elongated form it may be formed into a speral for treatment. The copper removed from the article is cathodically deposited. After removal of the copper coating continued electrolysis results in the formation on the article of an anodized oxide coating of zirconium without appreciable dissolution of zirconium or any interdiffusion alloy formed with the copper coating. Reference is made to removing copper coating from a zirconium alloy containing less than 6% of uranium. |
