Aloha, fun & authoritative answers -- no cost, no registration, no passwords, no popups
(as an eBay Partner & Amazon Affiliate we earn from qualifying purchases)

Where the
world gathers for metal finishing
Q&As since 1989

-----

Ammonium Phosphate forming on stainless steel

2004

White granular film was discovered on "Stainless Steel" material. Apparently the stainless steel is 304 grade. We are trying to get a contaminated part and have it analyzed for verification. A swap sample of contaminant was taken for analysis. Result indicated that the substance is Ammonium Phosphate Crystals. How could Ammonium Phosphate crystals form on Stainless Steel?

Are there any passivation processes, welding, or other processes that can cause this problem?

I appreciate any help.

Massoud Rezaei
Automated Material Handing - Salt Lake City, Utah, USA

I'm sorry but I don't quite understand, Mr. Rezaei. This fabricated material was in some unknown service environment after you built a machine from it? Or the incoming stainless steel from the mill doesn't look right? Certainly if it was used in an ammonium phosphate manufacturing or packaging environment this would happen.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

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: