ISO NSS. adv. auto technology banner. A discussion started in but continuing through Q. We have a customer, that we supply some zinc. Information to the interpretation of the result. The salt spray test is done according to DIN EN ISO (NSS). The paint thickness is measured. 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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If there is a minimum volume required by a particular salt spray test standard, this will be clearly stated and should be complied with. Although the majority of salt spray tests are continuous, i. Testing cabinets are manufactured according to the specified requirements here. I’ll really sio your help The number of cycle repeats and therefore the test duration is variable.
Equivalence between ASTM B-117 vs. ISO 9227 NSS
A discussion started in but continuing through Q. 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. Toby Padfield – Troy, Michigan.
Electroplated zinc-nickel steel is can last more than hours in NSS test without red rust or 48 hours in CASS test without red rust Requirements are established in test duration hours and coatings shall comply with minimum testing periods. Options include the following:. But which, is any, accelerated test is appropriate depends on what the finish is, and what you hope to test against.
So I will start with benchmark with these two standards. In dn automotive industry requirements are specified under material specifications. Most Salt Spray Chambers 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.
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 uso quality. Such details are provided in the appropriate product specifications. March 16, A. The neutral salt spray NSS test particularly applies to – metals and their alloys, – metallic coatings anodic and cathodic- conversion coatings, – anodic oxide coatings, and – organic coatings on metallic materials.
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. The longer the accelerated corrosion test, the longer the process remains out of control, and larger is the loss in the form of non-conforming batches.
They are not intended to be used for comparative testing as a means of ranking different materials relative to each other with respect to corrosion resistance or as means of predicting long-term corrosion resistance of the tested material. May 21, A. Life cycle A standard is reviewed every 5 mss 00 Preliminary. For example, a typical electroplated zinc and yellow passivated steel part lasts 96 hours in salt spray test without white rust. Proof sent to secretariat or FDIS ballot initiated: So if you want to know how to set up a salt spray cabinet or how to make the salt solution, then B is a reference.
Cyclic corrosion testing is better suited to this. Check out our FAQs. ISO gives the guidelines for proper measurement of corrosion resistance for hot-dip galvanized specimens. Remember that accelerated testing is not a proper indication of real world performance.
In either case, the exposure idn salt spray may be salt water spray or synthetic sea water prepared in accordance with the requirements of the test standard. Salt spray testing is popular because it is relatively inexpensive, quick, well standardized, and reasonably repeatable. The salt spray methods are all suitable for checking that the quality of a metallic material, with or without corrosion protection, is maintained.
Din En Iso .pdf
This climate is maintained under constant steady state conditions. These acidified test solutions generally have a pH of 3. Other test solutions have other chemicals added including acetic acid often abbreviated to ASS and acetic acid with copper chloride often abbreviated to CASS each one chosen for the evaluation of decorative coatings, such as electroplated isl, electroplated copper-nickel or anodized aluminum. Results are represented generally as dinn hours in NSS without appearance of corrosion products e.
Chamber volumes vary from supplier to supplier. This acceleration arises through the use of chemically altered salt spray solutions, often combined with other test climates and in most cases, the relatively rapid cycling of these test climates over time.
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. This is followed by 0.
This produces a corrosive environment of dense salt water fog also referred to as a mist or spray in the chamber, so nes test samples exposed to this environment are subjected to severely corrosive conditions. The principle application of the salt spray test is therefore enabling quick comparisons to be made between actual and expected corrosion resistance.