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Bio harmless electrolytes for surgical instrument etching

August 2, 2011

Hello,

I am conducting a project for a medical company which provides surgical instruments.They are interested in optimizing their etching process. Can someone tell me if there are electrolytes which are non-toxic for the body? The stainless steel is 316.

Thank you very much,

Andreea Feher
student - Swansea, UK

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Andrea

If the etching (and solution) is for marking the instrument, I would expect that a post etching passivation would be performed. Consider looking at ASTM F86. There are some electrolytes that are good for etching and found in soda pop; just not the same concentration. Just how non-toxic does it need to be, and how fast does it have to etch?

Willie ALexander
- Colorado Springs, Colorado
First of two simultaneous responses -- August 3, 2011

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Second of two simultaneous responses -- August 3, 2011

Hi Andria
The processes we use to etch any metal depends on the reason for etching, weight reduction, scale removal, surface finish etc. Knowing these, type choice is limited to what will do the job.
However there are two points to consider.
First; the final stage of any etching process is complete removal of all chemical residues.
Secondly, toxicologists do not recognise toxic chemicals as such - only toxic quantities.

Geoff Smith
Hampshire, England

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Just a few clarifications: The electrolytic etching is done for marking (logo, series) the surgical instruments. What we would like to do would be to shorten the process which includes etching with the electrolyte, neutralizing, washing and drying by eliminating the washing and drying step. That could be achieved if we can find a neutralizer, that is non-toxic enough so that it doesn't need washing.

Thanks in advance for more suggestions,

Andreea Feher
- Swansea, UK
August 5, 2011

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Correct me if I am wrong but it appears that you are hoping to say to a surgeon "We have found a cheaper way to make instruments. We don't wash them."
Please ask one (or a patient) and let us know the response.

Geoff Smith
Hampshire, England
August 7, 2011

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You have sliced to the heart of it, Geoff. All it would take is for a single patient to find out about this, and suffer a slower recovery than he hoped, and the instrument supplier would have a disaster on his hands.

Mooney's Law: "Every cost reduction program fails". Look for a better way to etch the instruments, not a cheaper way, and you'll often find that the better way costs less :-)

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
August 7, 2011

Have you looked into laser etch? No solution required.

James Watts
- Navarre, Florida
August 8, 2011

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September 13, 2011

Hello,

I would like to know if there is any database of chemical compounds that can be used as electrolytes and neutralizers for electroetching stainless steel. I have tried to find one, but was not successful.

Thank you,

Andrea Feher
student - Wales, United Kingdom

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September 13, 2011

Hello,

Can someone recommend me a book/article which treats the theoretical basis of metals etching -the chemical reactions- ?

Thank you,

Andy Feher
student - Swansea, Wales, United Kingdom