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

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

Home /
T.O.C. Fun
FAQs Good
Books Ref.
Libr. SITE
NEWS Help
Wanted Current
Q&A's Site 🔍
Search
finishing.com -- The Home Page of the Finishing Industry Search our quarter-million Q&As

Home of the finishing HOTLINE since 1989

-----

Corrosion protection of phosphate and oil




Hello, This is Jeff Martin Wintle. I am trying ascertain properly what offers the corrosion protection in the finish phosphate and oil. Is it the phosphate or the oil? Assuming the corrosion protection comes mostly from the oil, does the base phosphate offer any protection? Is there a difference betwixt zinc phosphate or mag phosphate?

Jeff Wintle
quality administrator - Birmingham, Alabama, USA
July 19, 2011


Hi, Jeff. This comes up absolutely constantly, with people forever wanting to know the salt spray resistance of bare phosphate, etc., so if you patiently search the site you'll find all kinds of insights. But, basically, the oil provides the corrosion resistance while the phosphate provides an adherent, amorphous or crystalline but absorbant base to hold the oil. So the effect is symbiotic. Without the oil, the phosphate does little; but without the phosphate, the oil can run off to too thin a covering for significant protection.

Today's phosphate coatings can be complex; there's no longer just iron, zinc and manganese, but tri-cationic and so forth, so the old axioms may not hold 100 percent anymore. But in simple generic terms, manganese are the thickest, iron are the thinnest, and the oil-holding capacity and corrosion resistance tend to be in proportion to the thickness of the phosphate coating.

Regards,

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Need quick confidential answers? $25
Need project assistance? $100/hr.
 July 20, 2011


What Ted said above per se', PLUS, if a hex chrome seal (do to send to Europe) is used with or without the oil the corrosion protection is greatly enhanced. Also the manganese process is usually used only for lubricity and metal "break-in".

robert probert
Robert H Probert
Robert H Probert Technical Services
supporting advertiser
Garner, North Carolina
probertbanner
July 21, 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:

Finishing
Jobshops Capital
Equipment Chemicals &
Consumables Consult'g,
& Software

About/Contact  -  Privacy Policy  -  ©1995-2026 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"