-- The Home Page of the Finishing Industry
Serious Education & the most FUN
you can have in metal finishing smiley

No popups, spam, registration or passwords
on this site
current topics
topic 5572

Passivation of 440


What is the best passivation process for 440c?

Dave Mortenson
Pullbrite, Inc. - Fremont, California USA


Electropolishing is considered the best way to passivate stainless steel. What particular application did you have in mind?

tom pullizzi portrait
Tom Pullizzi
Falls Township, Pennsylvania


We use the Type 8 formulation found in AMS2700 [link by ed. to spec at TechStreet], which is the same as the Type VIII found in the olde QQ-P-35C [link is to free spec at Defense Logistics Agency,]. 45-55% nitric acid in water, 120-130F, for 30 minutes minimum. We don't use a chromate dip afterward.

lee gearhart
Lee Gearhart

If you have a question in mind which seems off topic, please Search the Site

ADD a Comment to THIS thread START a NEW threadView CURRENT TOPICS

Disclaimer: It's not possible to 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 may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices

©1995-2018, Inc., Pine Beach, NJ   -   About   -  Privacy Policy
How Google uses data when you visit this site.