| 摘要 |
<p>The process comprises treating the surface of Al (alloy) with an alkaline soln. having pH >10 and contg. Ti ion and complexing agent, washing with water, and then treating with an acidic soln. contg. tannine or tannic acid as the main component. In an example Al alloy plate was spray with an alkaline soln. contg. NaOH of 7 g/l, 40% Ti sulphate soln of 1 g/l and Na gluconate of 1-8 g/l at 65/C for 6 sec. washed with water, spray with an acidic soln. contg. tannic acid of 50 g l at 55 degrees C ofr l sec. washed with water, and then dried.</p> |
