Aluminum alloy and Aluminum surface treatment methods

Aluminum and aluminum alloy surface treatment: 1. Degreasing treatment. Solvent wipe with damp cotton wool to remove oil, another with a clean cotton cloth can wipe several times. Commonly used solvents are: three vinyl chloride, ethyl acetate, acetone, methyl ethyl ketone and petrol.
Usually after proper treatment, metal surface with a high degree of activity, has again been easier to dust, moisture and other contamination. To this end, the treated metal surface should be carried out as quickly as possible bonding.
The different treatment of metal storage period as follows:
a Wet sand blasting brass, 8h.
b anodized aluminum alloy, 30 days;
c The blasting of the steel, 4h;
d Wet sand blasting treatment Aluminium Die Casting
e chromic acid - sulfuric acid treatment of aluminum alloy
f sulfuric acid treatment of stainless steel
Metal surface in a variety of heat treatment, mechanical processing, transport and storage process will inevitably be oxidized to produce a layer of uneven thickness of the oxide layer. Also vulnerable to oil pollution and adsorption of other impurities.
Oil and certain adsorbate, thin oxide layer can be successively with solvent cleaning, chemical treatment and mechanical processing, or directly with the chemical treatment. For the serious oxidation of the metal surface oxide layer thicker, it can not directly solvent cleaning and chemical treatment, and the best first mechanical processing.

a Degreasing solution after the chemical treatment of the following:
Sodium 10 non-ionic detergent 0.1 dipping at 65 C under 5min, then 65 ¡ã C following washing, and then distilled water washing and drying. Applicable to aluminum foil bonding.
10. Degreasing solution after the chemical treatment of the following:
Sodium fluoride a concentrated nitric acid at room temperature for 15 water-84 impregnated 1min, washed and then dealt with in the following solution:
Concentrated sulfuric acid 30 Sodium dichromate 7.5 Water 62.5 at room temperature, impregnated 1min, washed and dried.
b Degreasing solution, carried out after the following anodic treatment:
Concentrated sulfuric acid 22g / l in the DC intensity 1-1.5A/dm2 dipping 10-15min, and then in saturated potassium dichromate solution at 95-100 ¡ã C under dipping 5-20min, then washed and dried.
c Degreasing solution after the chemical treatment of the following:
Potassium dichromate 66 sulfuric acid (96%) 666 water, 1000 at 70 ¡ã C under dipping 10min, then washed and dried.
d Degreasing solution after the chemical treatment of the following:
Nitric acid (d = 1.41) 3 hydrofluoric acid (42%) at 20 ¡ã C under an impregnated 3s, that is washed with cold water wash, and then at 65 ¡ã C under washing with hot water, distilled water rinse and dry. This method is suitable for the higher copper castings aluminum alloy.
e Blasting or grinding after the anodization in the following solution:
Chromium oxide 100 sulfuric acid 0.2 sodium chloride 0.2 in 40 ¡ã C within 10min under the voltage from 0V rose to 10V, to maintain 20min, again, within 5min from 10V up to 50V, to maintain 5min, then washed, 700C drying. Note: the concentration of free chromium oxide may not exceed 30-35g / l.
f Degreasing solution after the chemical treatment of the following:
Concentrated sulfuric acid 27.3 Water 65.2 Potassium dichromate 7.5 dipping at 60-65 ¡ã C removed 10-30min after the water washing, drying or drying in 80 ¡ã C below; or in the following solution after washing to dry:
Phosphate 10 n-butanol 3 This method is applied to the water 20 PF - nylon plastic, etc. to good effect.
g Degreasing solution after the chemical treatment of the following:
Ammonium bifluoride 3-3.5 chromium oxide 20-26 sodium phosphate 2-2.5 concentrated sulfuric acid 50-60 boric acid 0.4-0.6 water 25-40 ¡ã C in 1000 dipping 4.5-6min, which means to wash and dry. This method is relatively high bonding strength, bonding within 4h after treatment for epoxy glue and epoxy - nitrile rubber bonding.
h Degreasing solution after the chemical treatment of the following:
Phosphate 7.5 Chromium oxide 7.5 Alcohol 5.0 Formaldehyde (36-38%), 80 in the 15-30 ¡ã C dipping 10-15min, and then 60-80 ¡ã C under the washing and drying.