| 摘要 |
Oxide deposits are removed from the surface of copper-base alloy article by immersion in an aqueous alkaline solution having a pH of 11-14 at a temperature between 40 DEG C and its boiling point for between 2 seconds and 10 minutes, and then immersing the article in an aqueous solution of ferric sulphate, or similar ferric salt of a mineral acid. The salt concentration is between 0.5 and 3.0 N, the period of immersion is at least two seconds, preferably 5 to 60 seconds, and the salt solution is at a temperature of 25 DEG to 95 DEG C, preferably 60 DEG to 90 DEG C. At the end of each immersion the article is drained, blow dried, and rinsed with water. |
