No passwords, no registration, no paywalls, no popups, no AI

As an Amazon Associate & eBay Partner we earn from affil links

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

Search our quarter-million Q&As

Home of the finishing HOTLINE since 1989

-----

Black stain after passivation, brown spots after stress relief on stainless steel

Hello everybody,
Sometimes we have brownish spots on 15-5 stainless steel after stress relief process and sometimes the same part has dark/black stains after passivation process, in other words these stains/spots are located all over the part when we received them from Stress relieve/passivisation process.
I checked out our internal processes like cleaning process, mfg process, and packaging process and also I have checked the passivation process which has done outside the company. But nothing has been found?

I would appreciate if you guys could assist me with this problem.

Thank you

Ali Zarrin
product designer - Valencia, California, USA
September 28, 2011

Sorry! Finishing.com is temporarily Read-Only.
Ted Mooney is retiring but I have several offers to take it over.
We're working hard to make sure we find it the best new home.

Disclaimer: It's not possible to fully 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 might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories: