finishing.com -- The Home Page of the Finishing Industry

HomeFAQsSuggested
Books
Help
Wanteds
Advertise
on this site
FORUM
current topics
Live! From beautiful Pine Beach New Jersey: Welcome to the world's most popular metal finishing website

topic 35573 p2

Acceptance criteria after salt spray test

adv.   auto technology banner


< Prev. page          (You're on the last page)


A discussion started in 2005 but continuing through 2019

November 21, 2016

Q. SIR,
REQUEST YOU TO PROVIDE SOME NUMERICAL VALUE (REQUIREMENT FOR SALT SPRAY TEST).

WE ARE DOING SALT SPRAY TEST AS PER ASTM B117 [link by ed. to spec at TechStreet] FOR REINFORCING BARS WITH EPOXY COATING FOR 96 hr AS WELL AS 204 hr.

CORROSION RATE INDEX (cri) CALCULATED.

AT PRESENT WE ARE GIVING ONLY MASS LOSS (g/m2) AGAINST UNCOATED SAMPLES -- BOTH WILL BE SUBJECTED TO TEST.

RADHAKRISHNA K rao
CIVILAID TECHNOCLINIC PVT. LTD - BANGALORE, KARNATAKA, INDIA


April 11, 2017

Q. Hello all.
The salt spray test results report shows at 96 hours 5 g and the customer said I wish 10 g on e-coat process; the raw material is cast iron. The question is, for this process is it possible to meet with zero corrosion during 96 hrs ASTM B117 test.

Santiago lorenzo
Industrial Finishing - Brownsville Texas


April 2017

A. Hi Santiago. I'm not understanding your usage of grams of corrosion, and the customer wanting more corrosion than you are getting -- something seems to be worded funny. But, yes, you can certainly get 96 hours of salt spray performance from proper pretreatment and e-coating.

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"



June 2, 2017

Q. Hello to all.
Please clarify the black spot observed in SS test what is this effect during testing time?

vijay_singh
VIJAY SINGH
lohia corp limited kanpur - kanpur uttar pradesh India


June 2017

A. Hi Vijay. Subramanian says it does not represent failure. I agreed except that if the customer specs says it's failure, then it's failure. Brian Terry tells us that some specs like AMS2404 [link by ed. to spec at TechStreet] define the appearance of any corrosion as failure, and that the spots might be corrosion and can be tested. Then too, one person's black spots may not look the same or be the same as another person's black spots.

Please explain your situation so it's less abstract. Thanks.

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"



November 30, 2017

Q. Hi sir,
Define salt spray test and how many hours test for door handle (Mild steel) and what is the conditions. Which standard we need to refer for corrosion resistance test on ferrous materials?

balaji krishnsamy
- trichy, tamilnadu, india


December 2017

? Hi cousin balaji. Please start with who you are, what you do, what type of plating or coating you are talking about, and what kind of door handle you are referring to (automotive interior, automotive exterior, home interior, home exterior lockset, etc.)

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"



January 20, 2018

Sir,
I want to know that in SS test what is method to check black corrosion on zinc plating. According to our product standard, conditions is 0.05% corrosion area of total test surface of base metal would be the passing criteria, so please help me can I consider black corrosion or spot as base metal corrosion or, if not, then what is the process to know base metal corrosion?

Shurveer singh
- Udaipur,raj. india



January 29, 2018

Q. Hello. I just want to ask you some help. Can you offer me any documents which I can get help while interpreting ss test results?
Thank you so much.

yunus sezgin
- istanbul TURKEY


January 2018

A. Hi Yunus. The most important document is the specification which the parts were processed according to. Very often this will tell you how to interpret the results. Interpreting the results for salt spray testing of aluminum conversion coating, various electroplated coatings, powder coating, etc., may be quite different. Please tell us what specification number the parts you are referring to were processed to. Thanks.

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"


January 29, 2018

Q. Hi TED;
thanks for answering.
We're processing fe-zn, fe-ni, fe-cr, cuzn-ni, zn-cr, zn-ni.

So I need something about these processes.

Thank you so much.
Regards.

yunus sezgin [returning]
- istanbul TURKEY


February 2018

A. Hi again, Yunus. You probably should find/choose a spec for each of those 6 processes (although I'm not sure what platings you are describing: Zn on Fe, Ni on Fe, Cr on Fe, Ni on Brass, Cr on Zn, Ni on Zn?).

In the USA we have MIL specs, ASTM specs, SAE-AMS specs and probably a few others. There are German DIN specs, Japanese JS specs, British BS specs, and ISO international specs. As previously mentioned, some of these specs will include interpretive guidelines for what constitutes failure in salt spray testing.

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"



February 4, 2018

Q. Dear all,

We are a manufacturer of metal parts and we have received complaints from customer about failure of salt spray test. They are claiming of 72 hrs SST and therefore we have forwarded the complaints to supplier. They have replied that the storage time is one of the factors that affect the test result since the product customer used has been stored for 6 months and the test is best performed within the period of 24 hrs after electroplating. We are not sure if there is any direct relationship for the result and time period.

May I ask if there is any time limit or requirements for salt spray test after the metal is freshly electroplated? Can supplier of electroplating guarantee period of time that the products can pass the test? I have heard of half year from the supplier but I'm not sure. Currently the supplier is claiming that the test should be best performed within 24 hours after electroplating. Thanks for all your support.

Vincent Lee
Wang Tak Metal Products - Hong Kong


February 2018

A. Hi Vincent. I'd be happy to hear to the contrary from any readers, but I side with your supplier. If the parts endured shipment by sea, or storage in a corrosive, damp, or smoggy industrial environment for 6 months they could very well be exhibiting corrosion signs which would fail an examination after salt spray even before they go into the salt spray chamber :-)

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"



February 23, 2018

Q. Hi, how are you.
We are producing mortise locks. We are using EN 1670 [link by ed. to English BS EN 1670 spec at TechStreet] for salt spray test results. So I want to know about rust. It says that there cannot be any spots larger than 1,5 mm in 650 mm2.
I don't know how to interpret that because which 650 mm2 area will I choose. I mean if there is a big plate and there is just one spot with 2 mm, what should I say. It is ok or not?
Thank you so much

yunus sezgin [returning]
kalekilit - istanbul TURKEY


February 27, 2018

A. Hi Yunus,

I would reject the part, the 650 mm^2 you select should be a large continuous surface (in this case it's a big plate). The corrosion pit is larger than the standard and you should reject. The bigger the pit the sooner it started corroding or the plating / supplemental coating was not thick enough to inhibit the corrosion that you're looking for.

Cheers.

Erick Leong
Vapor Bus International - Buffalo Grove, Illinois



March 16, 2018

Q. Hi, my name is Steven Sze. I'm an aluminium panel design engineer. The panels are mostly used for building cladding. Our company is about to have one of our steel panels tested (aluminium interior) against Salt Spray Test 1000 hours. May I know if there is any standard that we can refer to, to define if our product "Passed the test" or "Failed the test"?

Steven Sze
- Brisbane, Queensland, Australia


March 2018

A. Hi Steven. I assume these steel panels are painted or powder coated rather than galvanized? Hopefully a reader with architectural experience will understand your question better than I do, because I'm not "getting" this idea of an "aluminum interior". I don't think there is any possibility of a panel which is painted on one side but aluminum on the other passing a salt spray test which exposes both sides.

My reason for asking about the paint or powder coating is that the specifications for the coating, rather than the standards for how to conduct a salt spray test, is usually where to find the pass/fail criteria. So I don't think anyone can direct you to that pass/fail info until you describe the coating specification. Good luck.

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"


March 19, 2018

A. Hi Steven!

Maybe ISO 4628-3 [link by ed. to spec at TechStreet] (Paints and varnishes -- Evaluation of degradation of coatings: Assessment of degree of rusting) or ISO 4628-8 [link by ed. to spec at TechStreet] (Paints and varnishes -- Evaluation of degradation of coatings: Assessment of degree of delamination and corrosion around a scribe) can give you a reference to agree with your client the "fail" test.

You must always make an agreement with your client beforehand so you don't have problems in the future. I participated in many part developments (we make fasteners but I think it applies for everything) and when we had some problems with corrosion tests, it was about how the "fail" was assessed.

I think ASTM D610 [link by ed. to spec at TechStreet] (Standard Test Method for Evaluating Degree of Rusting on Painted Steel Surfaces) can help, too. In ISO 4628-3 there is a correlation chart so you won't need to get both standards for this one.

Best of luck and hope you solve this one!

Daniel Montanes
TEL - N FERRARIS - Canuelas, Buenos Aires, Argentina



March 15, 2018

Q. We are following ASTM B 117 and NADCAP regulations on our chamber and I occasionally have parts that get a brown stain that I have failed previously as rust. However, on my most recent test pieces, I submersed them in Copper Sulfate to plate them and they did NOT turn pink. We abrasive blast with aluminum oxide prior to passivation. Any ideas on what my brown stains are?

Thanks:)

Kyle Major
- Boss, Missouri, United States


March 2018

? Hi Kyle. I think we need to clearly understand what the substrate and finishing process are. Are we understanding these are stainless steel parts which have been passivated? Knowing the grade of stainless steel would be helpful.

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"


March 20, 2018

Q. The material is 300 series stainless steel that has been abrasive blasted and passivated.

Kyle Major [returning]
- Boss, Missouri, United States



How to QUANTIFY the extent of failure in salt spray test

August 11, 2018 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread

Q. My situation:
Anyone can help? How to quantify the failure in salt spray testing?

For suppose I found the failure at the last minute or if I see the failure at very little amount?
How to measure the extent of failure in the test.
Because I found the black coloured rust formation on the steel sheet within 140 hours.

Sri Raj
Tester - Puducherry, INDIA


August 2018

A. Hi Sri. You tried to post this under the subject of "Salt Spray Test -- ASTM B117 Operational Problems", but we moved your question here because ASTM B117 [link by ed. to spec at TechStreet] tells you how to operate the test cabinet, but it does not tell you what constitutes failure of tested parts. You find out what constitutes failure in the specification that you are processing to. That can be totally different for aluminum parts, stainless parts, steel parts plated with different materials, steel parts phosphatized or black oxided, steel parts powder coated, etc.

It is not your job as the tester to invent pass/fail rules; it is your job to find out where that "140 hours" requirement came from, read the spec that dictates that 140 hours, and determine whether the parts complied with the testing requirements for that processing specification.

I am not saying that the spec will be 100% free of ambiguity. You may well come back to us and say that you are still not sure whether the parts passed or failed … but we can't talk about it until we know what spec you are trying to comply with and what it says about the subject. Good luck!

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"



September 10, 2018

Q. Hi,

We have some bolts which are coated with Yellow dichromate. Does white rust appears in this case also?

Sandeep Pawar
- Syracuse, New York, USA


September 2018

A. Hi Sandeep. Please tell us who you are and what you do (plating shop employee, salt spray test lab, buyer, designer) and why you want to know. Then we'll have a starting point towards understanding your questions in a more useful way.

May we assume the bolts are steel? You can't apply yellow dichromate to steel, but you can apply it on top of cadmium plating, zinc plating, zinc alloy, and tin-zinc plating. So we have to assume that those bolts are plated. And all of those platings can generate white rust. So if your question was understood, the answer is yes, if those bolts corrode, it is possible for them to get white rust. Good luck.

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"


September 13, 2018

A. The only thing I can contribute is Cd or Ni plated bolts last a lot longer in salt spray when chromate coated. This is based on actual testing experience. Never had them in the chamber long enough to see a failure.

Ronald Zeeman
Coil Coating - Brampton, Ontario, Canada



November 15, 2018

Q. Dear all,
Our company uses coating Fe/Zn12/A/T2 on steel and zamak hardware. We start a discussion regarding evaluation of white rust. My question: how should we treat changing of part of coating surface to matte and grey/black color. I don't mean black spots, but whole areas. One of our laboratories claims it is white corrosion but I have doubts.

Anna Borowska Kos
- Gdańsk, Poland



February 6, 2019

Q. Dear sir,

Please share SST hours for Yellow Passivation of 8-10 micron thickness.
Also share details about what is top coat and why it is used

Shilsagar kedare
- Pune,Maharashtra,India


February 2019

A. Hi Shilsagar. Please share who you are what you do and why you want to know first, then people will probably be able to help you :-)

Pending your response, 192 hours salt spray should be a safe specification.

The world largely shifted from hexavalent chromating to trivalent over the last few decades, and most trivalent chromates cannot match the corrosion resistance performance of the hexavalent chromates without an additional top coat, which may be a titanium, zirconium, or similar final dip which helps seal the surface away from the environment. Good luck.

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
finishing.com
Pine Beach, New Jersey
Striving to live "Aloha"



If you have a question in mind which seems off topic, please Search the Site

ADD a Q, A, or Comment on THIS topic START an UNRELATED topicView CURRENT HOT TOPICS

Disclaimer: It's not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices


©1995-2019 finishing.com, Inc., Pine Beach, NJ   -   About finishing.com   -  Privacy Policy
How Google uses data when you visit this site.