×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Galvanic area effect/proximity

Galvanic area effect/proximity

Galvanic area effect/proximity

(OP)
I have a general galvanic corrosion question, I'm early in the design phase so I have no firm details as yet. I know a large anode/small cathode is ideal, but in general will the anode corrode faster at the contact point with the anode (e.g. a steel housing with a Ti connector body) or will the low electrical resistance of the anode allow for a more uniform corrosion of the anode ??  My thoughts are there will be little or no difference, am I right ?

Thanks for any input.

"You can observe a lot just by watching"
Yogi Berra

RE: Galvanic area effect/proximity

(OP)
Oops, I meant at the contact point with the cathode. Sorry for the poor proof reading.

"You can observe a lot just by watching"
Yogi Berra

RE: Galvanic area effect/proximity

I depends (I love saying that).
Are the two items connected? good contact? is there a seal or gasket?
What about the conductivity of the electrolyte?

In general there will be more attack next to the contact.  If there is fluid under the connection then you are really screwed.

= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
http://www.trent-tube.com/contact/Tech_Assist.cfm

RE: Galvanic area effect/proximity

(OP)
Hedging your bets I see :)  Actually I'm looking at threading a connector with a Ti body into a large 4130 steel housing, so the area ratio will be good. This will be sitting in ~600 meters of seawater, little or no current at that depth. I was initially thinking the area ratio would negate any dissimmilar metal corrosion problems of the steel, but I wanted some thoughts from folks who have some experience. It sounds like there will be more corrosion near the point of metal contact. Seems like I need to give this some more thought.

Thanks Ed

"You can observe a lot just by watching"
Yogi Berra

RE: Galvanic area effect/proximity

The critical area will be in the threads, where there is essentially a 1:1 surface area ratio.

I wouldn't recommend a threaded connection.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources