ASTM B633-98 PDF
ASTM B Type II and III zinc chromate plating Q&A’s. *Note: Answer is based upon pre versions of B (, , ). The revision. Hi, can anyone advise if the ASTM std ASTM B [link by ed. to spec at TechStreet] std specification for Electroplated coatings on Iron and steel, the . ASTM Be1 Standard Specification for Electrodeposited Coatings of Zinc on Iron and Steel Scope This specification covers requirements .
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August 31, A. Going with clear will make it difficult to tell what is clear chromated zinc vs. Some of today’s proprietary trivalent chromium coatings are very thin and consequently will not generate a highly saturated color though. No it does not imply that.
So if you need to color match, you need aastm do it with a requirement for compliance with sample parts — not a verbal description. We are getting poor coverage on the as-cast surface of some steel castings using a yellow Zinc chromate.
ASTM B – 98 Standard Specification for Electrodeposited Coatings of Zinc on Iron and Steel
Answer is based upon pre versions of B, Hi, I recently received 2 batches of parts from astj separate platers using this specification. The part is currently being produced in China and my local platers are suggesting a dye to get a blue color. Trivalent chromates give paler and lighter finishes; some use metals, some use permanganates, some use dyes, in order to replicate the Hex finish. Our plater would like to go to a clear zinc, but our customer is under the assumption that the clear will not do as good a job with v633-98 resistance and salt spray life.
Ray Kremer Stellar Solutions, Inc. What process variation would produce these different results? It’s not possible to diagnose a finishing problem or the hazards of an operation via these pages.
Could you explain this? Certain castings are difficult, if not impossible, to plate in either asmt or alkaline non-cyanide plating baths.
B Where service conditions are valid only for coatings with chromate conversion coating. A Blue with pale yellow is the best replacement for yellow as of now. Also, I found out that the casting is painted after plating. Zinc plated components vary from one industry to another. III zinc plating A discussion started in but continuing through Q. How do you know if it is supposed to be Zinc Yellow or Zinc Clear? Corrosion Resistance Requirements Types.
The revision addresses RoHS concerns and specifically allows non-hexavalent chromate treatments. Regarding the question asked in letter ; Type II zinc plating vs. All I need to know is what color the types are.
Surfaces left-bare should be heavily chromated. Olive Drab chromate is hrs.
Zinc Plating: ASTM B Type II vs. III
The answer is Yes. To determine the nature of accuracy or revision level please verify above data with current releases: Does anybody know this info? Regards, Ted Mooney, P. Different brands of chromate conversion chemistry, possibly different plating processes acid zinc vs. To me “bright blue” does not usually literally mean “bright blue” like the sky or a robin’s egg. SC 4 very severe. This applies to all metals.
ASTM B633-98 std: Electrodeposited coating of Zinc
Numeral indicates thickness in micrometers. Yellow chromate should get 96 hrs to failure. It still will have Hex Chrome.
So if I’m interpreting this correct, there is both a color difference and a salt spray difference. But if you are looking for something indisputably blue, as opposed to clear with a possible slightly bluish cast, this probably requires dye. Mark Hollenbeck alloys – Muskegon, Michigan A.
Also, some yellow chromates are clear w. I will be attending the ASTM B8 committee meetings in Philly later this week and will mention this letter to the sub-committee chair responsible for the B spec. Can anyone give me some direction on how to get the customer to accept going to clear. What do you say? I’ve seen this done less commonly on chromated zinc plating than on chromated aluminum.
No, other colors may not be available if my presumption is right.
Not the least of which is the environmental regulations impact on the future of the selected finish. As the USA moved toward metric fasteners, for a while there was a move to dye them blue. I have the exact same questions.
To calculate it is very difficult, as the plating atm a few molecules thick.
ASTM B-633 Type II vs. III zinc plating
In 24 years I have only been asked this question once before and I presume it involves phosphating over zinc plating for those heavy phosphating grammage applications, where normal phosphating will not provide enough zinc phosphate that is required in the deposit. ASTM B and all other worldwide standards were written around the time when no one spoke about trivalent.
Zinc plating is usually considered a functional coating, not a decorative one. It definitely implies Hex Chrome.