| 摘要 |
Aq. electrolyte, for electrolytic roughening of Al or Al alloy sheets, esp. for Se rectifier prodn. consists of 0.5-3 wt.% HCl and 10-2000 (300-500, esp. 50-150) mg/l Ni++, pref. used under A.C. conditions, the sheets being connected to the earth line at 20-80 amp/sq.dm. current strength, at 20-50 (pref. 37) degrees C. Sheets are pref. chemically after-treated with a mixt. of 0.5-20 pref. 10 wt.% H3PO4, 0.1-10, pref. 3 wt. % HCl and 10-2000 mg/l Ni++, pref. at 20-100 degrees C, pref. 85 degrees C. Ni may be replaced with equimolar amounts of Fe or Co. When using sheets for Se rectifier mfr. after-treatment is pref. followed by electroplating with a Ni layer. |
