There are three distinct test method in ISO the neutral salt spray (NSS), the acetic acid salt spray (AASS), and copper-accelerated acetic. ISO NSS. adv. auto technology banner. A discussion started in but continuing through Q. We have a customer, that we supply some zinc. The salt spray (or salt fog) test is a standardized and popular corrosion test method, used to Other important relevant standards are ISO, JIS Z and ASTM G The most common test for steel based materials is the Neutral Salt Spray test (often abbreviated to NSS) which reflects the fact that this type of test.
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Hi David, There are several differences between the two specifications, including salt concentration range, salt analysis, water quality, angle of inclination of test panels, corrosivity requirements, I think the temperature is about the only thing that has been standardised.
These standards describe the necessary information to carry out this test; testing parameters such as temperature, air pressure of the sprayed solution, preparation of the spraying solution, concentration, pHetc. A discussion started in but continuing through Q. For example, a typical electroplated zinc and yellow passivated steel part lasts 96 hours in salt spray test without white rust.
We did tests of our products under ISO What do you want to test? This produces a corrosive environment of dense salt water fog also referred to as a mist or spray in the chamber, so that test samples exposed to this environment are subjected to severely corrosive conditions.
The zinc carbonates are not produced when a hot-dip galvanized specimen is exposed to a salt spray fog, therefore this testing method does not give an accurate measurement of corrosion protection.
Corrosion tests and standards: I am needing to know if a gradual table of corrosion in assay exists of Salt Spray, if this table exists and if anyone would be able to post it, I will be thankful.
Equivalence between ASTM B-117 vs. ISO 9227 NSS
Is there any equivalence between this two standards? Test duration depends on the corrosion resistance of the coating; generally, the more corrosion resistant the coating is, the longer the period of testing before the appearance of oxides.
Is it possible to reduce test duration by some accelerated Testing? This acceleration arises through the use of chemically altered salt spray jss, often combined with other test climates and in most cases, the relatively rapid cycling of these test climates over time. Such details are provided in the appropriate product specifications.
The salt fog fall-out rate is verified by using a minimum of two 80cm 2 funnels nds salt spray atomiser, each inserted into a measuring cylinder graduated in ml.
A personal good afternoon to all, I am Jose of Curitiba, I am a painting inspector, I am a specialist in the area of Salt Spray, and have a problem and knowing of the competence of all readers in corrosion, perhaps they can help me. For this reason the salt spray test is most often deployed in a quality audit role, where, for example, it can be used to check the effectiveness of a production process, such as the surface coating of a metallic part.
Monday to Friday – Oso are represented generally as testing hours in NSS without appearance of corrosion products e. The principle application of the salt spray test is therefore enabling quick comparisons to be made between actual and expected corrosion resistance. You will then need to talk to your customer about the possibility of using one specification in lieu of the other.
This test can be used to test the relative resistance to corrosion of aluminium alloys when exposed to a changing climate of acetic acid salt spray, followed by air drying, followed by high humidity, all at an elevated temperature. From Wikipedia, the free encyclopedia. Website design by Peter Bourne Communications. All information presented is for general reference and does not nsz a professional opinion nor the policy of an author’s employer.
Although there may be a weak correlation between the duration in salt spray test and the expected life of a coating hss certain coatings such as hot dip galvanized steelthis test has gained worldwide popularity due to low cost and quick results.
Salt spray test – Wikipedia
Failure to meet this requirement implies instability in the chemical process of the pre-treatment, or the paint quality, which must be addressed immediately, so that the upcoming batches are of the desired quality.
Test specimens are placed in an enclosed chamber, and exposed to 1 of 2 possible changing climate cycles. ASTM G85 is the most popular global test standard covering modified salt spray tests. Most commonly, the time taken for oxides to appear on the samples under test is compared to expectations, to determine whether the test is passed or failed.
Variations to the salt spray test solutions depend mss the materials to bss tested.
You need to upgrade your browser You are using Internet Explorer 8 This is considered an out of date browser. Test specimens are placed in an enclosed chamber, and exposed to a changing climate that comprises the following 3 part repeating cycle.
The appearance of corrosion products rust or other oxides is oso after 922 pre-determined period of time. Hi Sergio, ASTM B does not address corrosion behavior of test specimens, but describes the parameters for conducting a salt spray test.
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Such tests are commonly referred to as modified salt spray tests. Most Salt Spray Io today are being used NOT to predict the corrosion resistance of a coating, but to maintain coating processes such as pre-treatment and painting, electroplating, galvanizing, and the like, on a comparative basis.
The salt spray methods are all suitable for checking that the quality of a metallic material, with or without corrosion protection, is maintained.