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

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

-----

Spotting on Zinc Phosphated GI Sheet

We are manufactures of panels, and in our painting line, we face a problem while zinc phosphateing on GI Sheets. White spots appeared on the surface after treatment. It happen only in GI after 7-10 days after fresh bath makeup. Please give a solution

Shihab
Trading - Saudi Arabia
2005

YOU MUST CHANGE YOUR PHOSPHATING SOLUTION,THE KEY QUESTION IS PHOSPHATING FORMULATION.

Mi Dewei
WCSM - Wuhan, China
2005

Hi Dewei,
Could you spend a little more time to explain your idea?
What is the root cause for the white spots forming?
What is its chemical composition and metallurgical structure? How much it affect part anti-corrosion performance?

Thanks,

Bill Wang
- Guelph, Canada
2006

(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: