What is the cause of loose film when the aluminum profile is black at room temperature? How to deal with it?

The reason:
1 Dacă degresarea și curățarea nu sunt temeinice, filmul negru format după întărire va cădea dacă este șters ușor;
2 activation is not good;
3 blackening time is too long;
4 dilution ratio is small, the solution content is high, and the nitrite content is high;
5 solution acidity is high; &n aluminum alloy building profile insulation profile bsp;
6 copper replacement is fast, insufficient additives;
7 oil immersion time is short.

1 Strengthen pre-treatment, pay attention to degreasing and cleaning;
2 After degreasing, the parts must be fully activated, not only to neutralize the residual lye on the surface, but also to activate the metal surface and increase the bonding strength between the film and the substrate;
3 reduce timpul de înnegrire,
4 to strictly dilute the formulation solution according to the formulation requirements;
5 poate fi neutralizat cu NaOH;
6 add additives;
7 extend the oil immersion time.