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





-----

Hydrogen embrittlement of aluminum castings





September 9, 2010

I am designing a casting which will be exposed to hydrogen gas. My preference is to use aluminum for weight and cost consideration but am concerned about Hydrogen Embrittlement.
Is there a surface finishing process either a coating or plating method that would seal the surface from hydrogen gas and hydrogen embrittlement of the aluminum casting?

Matt Carroll
castings designer - Sandusky, Ohio, USA



simultaneous replies

Why do you think that aluminum will suffer from hydrogen embrittlement?
Even medium hard steel does not suffer from it.
Hard high tensile strength steel does, but aluminum is not even close in either of these areas.

James Watts
- Navarre, Florida



Sir:

I had one practical experience with hydrogen embrittlement. In a hot dip galvanizing shop a worker threw some aluminum outboard engine propellers into a caustic tank to clean them. After an hour or so the propellers were brought out of the caustic and dumped on the floor. Most of them broke into several pieces.

I asked a guy who was supposed to be knowledgeable and he said that atomic hydrogen (a hydrogen atom which is very small) was formed on the surface of the aluminum and migrated into the castings and found other hydrogen atoms and formed hydrogen gas (H2) and became bigger and more and more hydrogen gas was formed inside the aluminum castings until the pressure caused the castings to break upon shock from hitting the floor. Thus I wonder if molecular hydrogen gas could even enter into the aluminum castings. Frankly I do not know, but I expect an expert metal guy would know.

Regards,

Dr. Thomas H. Cook
Galvanizing Consultant - Hot Springs, South Dakota, USA



September 11, 2010

Hi,

A quick googling shows claims and counterclaims about whether hydrogen embrittlement of aluminum exists as a practical problem, and whether hydrogen gas can offer the monoatomic hydrogen responsible for it -- but I am not a metallurgist either.

(Caustic readily dissolves aluminum. It is often used to strip the anodized layer off of aluminum, but timing is important in order to not destroy the aluminum object. Some complicated hollow parts are built by electroforming nickel onto aluminum mandrels and then completely dissolving the aluminum in caustic).

Regards,

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


none
finishing.com is made possible by ...
this text gets replaced with bannerText
spacer gets replaced with bannerImages

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    -    ©1995-2023 finishing.com, Pine Beach, New Jersey, USA