No registration, no passwords; no pop-up ads -- just aloha, fun, & authoritative answers.
As an eBay Partner & Amazon Affiliate we receive compensation for qualifying purchases.
Home /
T.O.C.
FAQs
 
Good
Books
Ref.
Libr.
Advertise
Here
Help
Wanted
Current
Q&A's
Search 🔍
the Site
pub  Where the world gathers for
plating, anodizing, & finishing Q&As since 1989





-----

Anodising LM24 Die cast Alloy




Dear Friends ,

I want the following information regarding Anodising of LM24 Die cast Alloy.

Pls inform us the cleaning process and anodising process for clear anodising of above Alloy.

Presently we tried with regular sulfuric bath with caustic etch,we found gray colour coating instead clear,pls inform us.

Thank you,

ELANGOVAN DAMODARAN
- INDIA
1999



You do not have a 'problem', what you have is a typical anodising response of sulfuric acid anodising on LM24 castings.

LM24 has a 'high' Si (silicone)content. In simple terms when oxidation takes place the Si atoms oxidise as well as the Al atoms and the silicone oxide particles are incorporated within the anodic film.

However unlike Aluminium Oxide which is translucent (which gives you the 'clear' finish that you are familiar with) Silicone Oxide particles are not and they appear as black specks in the anodic film. When you get enough black specks within your clear film the overall effect is a grey finish rather than a silver one.

Good luck!

The only real advice I can give is to change to an alloy such as LM5 (which your casting supplier probably won't like dealing with because it is harder to cast) and keep the anodic film thickness to a minimum that satisfies the technical requirements.

Peter Hirst
- UK
1999




(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:

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


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"