GB/T 8753-1988 Anodic oxidation of aluminium and aluminium alloys - Assessment of the loss of adsorption capacity of anodic oxide films after sealing - Staining spot test after acid treatment GB/T8753-1988 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Anodizing of aluminium and aluminium alloys-Estimation of loss of absorptive power ofanodic oxide coatings after sealing-- Dye spot test with prior acid treatment
Anodizing of aluminium and aluminium alloys-Estimation of loss of absorptive power ofanodic oxide coatings after sealing-- Dye spot test with prior acid treatment This standard specifies the use of the staining resistance after acid treatment to assess the sealing quality of anodic oxide films. UDC 669.718. 915
.111.2
GB875388
Iso 2143--- 81
This standard is applicable to the inspection of anodic oxide films that are intended to work in atmospheric exposure and corrosive environments, and is more applicable to the inspection of pollution-resistant oxide films.
This standard is not applicable to the inspection of oxide films formed on high-copper and high-silicon (Cu>2%, Si>4%) aluminum alloys; oxide films sealed with potassium dichromate; oxide films treated with oiling, waxing, and painting, dark oxide films, and oxide films with a thickness of less than 3um. When the sealing bath contains nickel cobalt or other organic additives, the anti-staining ability of the oxide film may be reduced. If there is a question about the sealing quality at this time, the arbitration test method for inspecting the sealing quality can be used to evaluate it. This standard is equivalent to ISO2143-1981 "Aluminum and aluminum alloy anodic oxidation-assessment of the loss of adsorption capacity of anodic oxide film after sealing
Staining spot test after acid treatment".
1 Principle of the method
The anti-color adsorption ability of the anodic oxide film is the basis for evaluating the sealing quality. Generally speaking, strong anti-staining ability indicates good sealing quality; but sometimes when the anti-staining ability is slightly reduced, it does not mean that the oxide film quality is poor, because the anti-staining ability is sometimes related to other factors.
The test is carried out on the degreased surface of the specimen. First, it is treated with acid, then stained with a dye, and finally the staining is observed and an assessment is made based on the result diagram of the stain spot test (Figure A1). 2 Solution
The test solution should be prepared with analytically pure reagents and distilled water (or deionized water). The acid solutions listed in 2.1.1 and 2.1.2 can be equally applied to any stain spot test. As for the solutions specified in 2.1.2, they are mainly for greater safety. 2.1 Acid solution
Store the acid solution in a container made of fluorosilicic acid resistant material, and be careful when operating. 2.1.1 Acid solution A
Each liter contains the following substances:wwW.bzxz.Net
Sulfuric acid: 25 ml (pza = 1.84 g/ml);
Potassium fluoride: 10 g.
2.1.2 Acid solution B
Contains the following substances per liter:
Approved by China National Nonferrous Metals Industry Corporation on February 4, 1988 and implemented on February 1, 1989
GB8753-88
Fluorosilicic acid (H,SiF.): 25 ml (pzo = 1,29 g/ml)2.2 Dyeing solution
Use the following dyeing solution to dye the oxide film after acid treatment. 2.2.1 Dyeing solution A
Contains the following substances per liter:
Aluminum blue 2LW (blue dye with international color number 69): 5g. Use dilute sulfuric acid or dilute sodium hydroxide solution to adjust the solution to a pH range of 5.0±0.5 (temperature is about 23℃). 2.2.2 Dyeing solution B
Contains the following substances per liter:
Sannodel Red B3LW (acid red with international color number 331) or aluminum red GLW: 10g. Use dilute sulfuric acid or dilute sodium hydroxide to adjust the solution to a pH range of 5.0±0.5 (temperature is about 23°C). 3 Test specimens
Test specimens are generally selected directly from production parts. If specially prepared specimens are used, even if they are the same as the production process, some erroneous results will be produced.
4 Test steps
4.1 Wipe the surface of the specimen with a cotton ball dipped in acetone, keep the surface of the specimen clean, dry and place it horizontally. 4.2 Drop a drop of acid solution A or acid solution B on the surface of the specimen. And keep it accurately for 1 minute (the temperature of the test solution is about 23°C).
4.3 Remove the acid drop, and wash and dry the surface of the specimen. 4.4 Drop the dye solution A or dye solution B (2.2.1 or 2.2.2) on the spot treated with acid, and keep the solution on the specimen for exactly 1 minute.
4.5 Wash off the dye droplets, and wipe the test surface of the specimen thoroughly with a clean cloth soaked in the suspension solution (about 20 seconds). Then rinse carefully and dry.
Note: The suspension solution is made of water and a soft abrasive, where the soft abrasive is magnesium oxide, etc. 4.6 Inspect the surface after the test and compare it with the result chart of the dye spot test, and then evaluate the degree of dyeing. 5 Results display
According to the result chart of the dye spot test, indicate the degree of loss of adsorption capacity; you can also fill in the grade value of dyeing intensity according to the result chart of the dye spot test.
Test report
The test report should include the following contents:
This standard number;
The shape of the sample,
The technical conditions of anodizing of the sample;
The acid treatment method used in the test:
The dyeing solution used in the test;
According to the result diagram of the dyeing spot test, fill in the degree of loss of adsorption capacity or the level of dyeing intensity; some other relevant tests or surface spot conditions, such as uneven dyeing. Aluminum blue
Additional notes:
GB8753--88
Result diagram of dyeing spot test
(Supplement)
This standard was drafted by Northeast Light Alloy Processing Plant. The main drafters of this standard are Gao Kangzhi and Wang Ziyi. Adsorption capacity
Degree of loss
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.