Salt spray test chamber | Common neutral salt spray test standard analysis

Salt Spray Test Standards

ASTM B117-2011: Standard test method for operating salt spray tester 1;

GB/T 10125-2012/ISO 9227:2006 Artificial atmosphere corrosion test Salt spray test;

GB/T 2423.17-2008/IEC 60068-2-11:1981 Environmental testing of electrical and electronic products Part 2: Test methods Test Ka: Salt spray;

GB/T 2423.17-2008 and GB/T 10125-2012 Neutral Salt Spray Test The difference is not much, according to the conditions of the product need to choose the salt spray test chamber, the following is the standard analysis:

Purpose and scope

The neutral salt spray test is suitable for comparing the resistance to salt spray corrosion of specimens with similar structures, and is also suitable for assessing the quality and uniformity of protective coatings. When used, the following limitations should be considered.

a. This test is not suitable as a generalized salt spray corrosion test;

b. The test is also not suitable for the evaluation of individual specimens for use in salty atmospheres.

For equipment and components, the test provides more realistic test conditions and evaluation methods for individual specimens. However, if in some cases, to ensure quality, the relevant specification requires individual specimens to be subjected to this test method, the specimen should be tested as part of the whole assembly or equipment together with the actual protective equipment (case, cover, jacket, etc.).

Test conditions

Note: The ± tolerances given are the permissible operating fluctuations, defined as the positive and negative deviations from the sensor setting at the operating control set point under equilibrium conditions. This does not mean that the set point can be varied by adding or subtracting the amount indicated by the given value.

A trial run to confirm test conditions should be conducted for at least 24 hours before testing begins. If the time between tests is 5 days or less, a trial run is not required if mutually agreed upon with the customer. Measurements of the test conditions should be taken immediately after the trial run and before the specimen to be tested is exposed. Care should be taken to measure only solutions that have not been subjected to significant evaporation. After confirming that the test conditions are within the specified range, stop spraying the salt solution, fill the salt spray test chamber with the test specimen and start the test. Evaporation of the solution collected in the measuring chamber and during the measurement can have an effect on the concentration and pH value.

Place at least two clean and dry collection devices in the test area where the specimen is to be placed, one close to the spray inlet and one away from the spray inlet. Additional collection devices can be used for more accurate spray uniformity mapping. The collection devices shall be placed so that they are not obscured by the test sample and therefore only collect mist, not liquid falling from the sample or salt spray test chamber section. Each collection device shall collect an average of 1.5 ± 0.5 mL/h of spray solution over a period of at least 24 hours. In addition to a trial run prior to the test, it is recommended that the collection rate be monitored daily for the duration of the test, if feasible. (Note: The number of additional collection devices placed is proportional to the chamber exposure area. For optional daily monitoring, fewer collection devices are typically used.)

The concentration and pH of the solution collected in each collection device should be within the ranges given in Table 1.

During operation, the solution tanks should be covered to prevent dust or other contaminants from affecting the solution and to prevent fluctuations in sodium chloride concentration and pH.

Duration of the test

The duration of the test shall be as specified in the relevant specification. It needs to be selected from 16 hours, 24 hours, 48 hours, 96 hours, 168 hours, 336 hours, 672 hours.

Minimize interruptions of the test. If it is not possible to replenish the salt solution in the salt spray test chamber, the chamber shall be opened only for simple visual inspection of the samples and shall be opened only for the replenishment of the salt solution. The total opening time shall not exceed 1 hour per day.

Periodic visual inspection of the sample under test may be carried out for a predetermined period of time, provided that the surface under test is not disturbed and the salt spray test chamber is open for the minimum time necessary to observe and record any visible changes.