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Chemical etching of brass

We have coldworked brass parts with fine holes at the top of the article. We need a suitable chemical etching process, little intensive than shot blasting, so that it can be seen clearly.

Rama subramanian
Plating shop employee - Bangalore , India
August 4, 2010

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Hi, Rama.
To be clear, you are looking to etch these parts for metallurgical examination?

Regards,

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

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August 13, 2010

No Mr.Ted Mooney.

I wanted to increase the brilliance of brass by chemical etching process.

Rama subramanian [returning]
- Bangalore, India
August 9, 2010

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August 17, 2010

I still may be misunderstanding, but it sounds to me like etching would preferentially attack the small holes and pits, making it highly unlikely that you can correct for them by etching. I think you need to either stop the coldworking process from creating holes in the parts, or re-polish the material. Good luck.

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

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August 18, 2010

Yes, Mr.Ted Money

I want to increase the depth of the cold formed parts with chemical etching process. Kindly suggest the right etchant.

Thanks and regards,

Rama subramanian [returning]
- Bangalore

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I WOULD SUGGEST A CHROMIC ACID DIP IN A SOLUTION OF CHROMIC ACID @ 250 GMS/LITER AND sulfurIC ACID IN RATIO OF 1:100 TO CHROMIC ACID AT AN TEMPERATURE OF 45-55 °C, IF THERE IS ANY SCALING, PRIOR HCl ACID PICKLING MAY BE SUGGESTED THEN WATER RINSE FOLLOWED BY DRYING
BEST LUCK

MAHENDRA GARGATTI
- BELGAUM, KARNATAKA, INDIA
November 13, 2010