ASTM B is the most widely adopted standard for salt spray testing. This standard is issued under the fixed designation B; the number 2 For referenced ASTM standards, visit the ASTM website, , or. Anybody could tell me what’s ” ASTM B [link by ed. to spec at TechStreet] SALT SPRAY TESTING” for zinc coating? What’s the specification for testing?.
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Is it typically a visual inspection?
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. The end-point of the test is often user-driven. ASTM G85 is the most popular global test standard covering modified salt nroma tests. Usually, the materials to be tested are metallic although stone, ceramics, and polymers may also be tested and finished with a surface coating which is intended to provide a degree of corrosion protection to the underlying metal.
What do you want to test? Retrieved from ” https: However, visual inspection is often more than enough.
Options include the following: This website has been developed with modern browsers in mind to allow it to display at its best in a wide variety of viewing situations – including mobile viewing. 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.
Test specimens are placed in an enclosed chamber, and exposed to 1 of 2 possible changing climate cycles. This test can be used to test the relative resistance to corrosion paints on steelwhen exposed to a changing climate of dilute salt spray at ambient temperature, followed by air drying at and elevated temperature.
Cyclic corrosion testing is better suited to this. Test specimens are placed in an enclosed chamber and exposed to a continuous indirect spray of salt water solution also referred to as fog or mist which falls-out on to the specimens at a rate of 1. For example, galvanizing is the most proven of all finishes, with real-world structures that have been protected for a hundred years in bad conditions 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 solution is prepared to a neutral pH of 6.
But which, is any, accelerated test is appropriate depends on what the finish is, and what you hope to test against. For example, a typical electroplated zinc and yellow passivated steel part lasts 96 hours in salt spray test without white rust.
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. These collectors are located inside the chamber, nominally at the same height as the test samples, one located close to the atomiser and one located away from the atomiser, in accordance with the positions specified in ASTM B, but also taking into account the chamber manufacturers defined work-space.
Regards, Ted Mooney, P. This is just food for thought, not a scenario I fully embrace, but consider: So this information should not be used as a substitute for referring to a complete test standard, at an appropriate revision level.
Typical Application This test can be used to test the relative resistance to corrosion of coated and uncoated metallic specimens, when exposed to a salt spray climate at an elevated temperature. A discussion started in but continuing through Q. Electroplated zinc-nickel steel parts 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.
This is followed by 2. Requirements are agreed between customer and manufacturer. Testing cabinets are manufactured according to the specified requirements here.
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.
There is a general historical consensus that larger chambers can provide a more homogeneous testing environment. Second of three simultaneous responses — A. August 27, Hi Sunil. The salt spray test has little application in predicting how materials or surface coatings will resist corrosion in the real-world, because it does not create, replicate or accelerate real-world corrosive conditions.
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. In this case, it would have been March 16, A. First of two simultaneous responses — A.
This is followed by 1. This is compared to expectations, to determine whether the test is passed or failed. The pH of the salt solution fall-out should be maintained at a neutral pH pH 6.
First of three simultaneous responses — A. Joshua Pires – Vancouver, B. ASTM G85 annex A1 — Acetic Acid Salt Spray Test non-cyclic This test can be used to determine the relative resistance to corrosion of decorative chromium plating on steel and zinc based die casting when exposed to an acetic acid salt spray climate at an elevated temperature. But regardless of what you think or I think, tests don’t have any merit if they include uncontrolled variables.
The salt spray or salt fog test is a standardized and popular corrosion test method, used to check corrosion resistance of materials and surface coatings.
It is also regularly updated, by an active and broad based ASTM sub-committee, so it is a standard that is continuously evolving. That’s the only way to know for sure.