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Acid etched surface area calculating method

2005

Dear friends
I need to know mathematically differentiation formula or method of acid etched surface area calculating method of aluminum, copper and stainless steel (304 -316 series) metal sheets.
any idea...
thanks,

Zafer Ersalan
gurkan constr.co - Turkey

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Sorry, I don't quite understand your question, Zafer. Please try to put it in context. Thanks.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005

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2005

Dear Ted
There is dramatically difference between polished and acid etched surfaces. For example if the polished surface area is 1 sqmeter,same surface area will be 1.5 or 2 sqmeters
when acid etched cause of roughness made by acids.Roughness depends on percentage,time,heat,kind of acids, etc. but I want to know calculating/measuring method of the difference if there is.
thank you.

Zafer Ersalan
- Turkey

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Pls reply my letter no. 37532. I tried to explain.

thanks.

Zafer Ersalan
- Turkey
2005

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Hello again, Zafer. I tried my best to answer the same type of inquiry--although in a very different context--in letter 32363.

I do not think I quite agree with you. The area of the smooth surface is 1 square meter only as a mathematical construct, not as a hard physical reality. What is the surface area of a sponge, or an ounce of activated carbon or diatamaceous earth? I say there is no answer; that is always depends on what scale you want to view the thing at.

I do applaud your effort to try to relate surface area to roughness, and agree that it has great value in a lot of contexts, for example how much dragout will adhere, how much etchant is consumed per minute, how fast a given chemical reaction will occur, etc. But I believe that the only route to success will be empirical data because the empirical data takes into account the fluid dynamics of the particular situation. If you try to quantify the surface area independent of the fluid dynamics of a situation, the only answer to the question is metaphysical: "how many angels can dance on the head of a pin".

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey