Organic and inorganic composite aluminium alloy non-chromium passivation treatment fluid

[0024] The main components of the organic and inorganic composite passivation solution with ferrate as the main inorganic salt are:

[0025] Potassium ferrate 0.7g

[0026] Phosphoric acid 0.5g

[0027] Waterborne Polyurethane 150g

[0028] Sodium silicate 10g

[0029] Deionized water 838.8g

[0030] The substrate used is aluminum alloy. The coating process is pH 4, dip-coating at room temperature, and drying at 150°C for 5 minutes.

[0031] The comparative examples are untreated aluminum alloy and chromate treated aluminum alloy.

[0032] figure 1 Polarization curves of various passivating solutions. Depend on figure 1 It can be seen that the corrosion resistance of the present invention is significantly improved compared with the blank sample, and is also equivalent to the passivation result of chromate.

[0033] The neutral salt spray test of the passivation film can reach 72 hours, and the adhesion can reach level 1.

[0035] Potassium ferrate 1g

[0036] Waterborne Polyurethane 150g

[0037] Phosphoric acid 0.5g

[0038] Sodium silicate 4g

[0039] m-xylylenediamine 3g

[0040] Deionized water 841.5g

[0041] The substrate used is aluminum alloy. The treatment process of the coating is pH 4, dip-coating at room temperature, and drying at 100° C. for 5 minutes.

[0042] The neutral salt spray test of the passivation film can reach 72 hours, and the adhesion can reach level 1.

[0043] In a word, the experimental results show that the passivation solution of the present invention can be used to obtain a passivation film with excellent adhesion on the metal surface. Stronger, so it can replace chromate, and in some respects, permanganate to achieve an environmentally friendly passivation film.

[0044] Because the passivation solution of the present invention does not contain chromate, it not only greatly reduces environmental pollution, but also meets the requirements of WEES and ROHS instr