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!

*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.

Jobs

Best thermally conductive paste for galvanized steel heat sink?

Best thermally conductive paste for galvanized steel heat sink?

(OP)
Using some snap on radiators around galvanized tubes, as seen here...



Those radiators are also galvanized steel, same as the tubes, though
in that photo the tube looks to already be painted.

I need to maximize the thermal conductivity between the two surfaces.

Radiators don't easily move when snapped down, so not looking so much
for an adhesive here, as whatever will best conduct heat between them.

If a consideration, the Delta T at the maximum will be 70F as the temp
inside and outside pipe ranges from 35F to 105F.

Some radiators will also have water flowing by them at < 100 PSIG and
under 15 gpm, if that plays into thermal paste selection to minimize
risk of having it eroding away.

Appreciate any suggestions, thanks!

RE: Best thermally conductive paste for galvanized steel heat sink?

What do you mean by "best?"

Your flow and pressure requirements imply a "glue" and not a "paste." What is service life?

Seems to me the go-to answer is a copper-filled or silver-filled epoxy:
http://conductivex.com/Flexible-Copper-Silver-Ther...

However, since water can erode pretty much anything, your service life may be limited. Your best bet might be to form a metal dam around the epoxy joint.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: Best thermally conductive paste for galvanized steel heat sink?

(OP)
By "best" I mean, for this application, ideal for maximum galvanized to galvanized thermal conductivity where water passage may be an erosion issue.

I'd qualify it further to add that it needs to be readily commercially available and not exorbitant where only NASA can afford.

I'd assumed that some conductive coatings are better suited for some particular types of metals and environments than are others.

RE: Best thermally conductive paste for galvanized steel heat sink?

If this is a "radiator" a galvanized surface is a poor choice, as "shiny silver" means reflective, which is the opposite of a good radiator. These could be worse than doing nothing. And steel is not usually used for heat transfer except at much higher temperatures than you mention.

This type of heat transfer assemble would normally be soldered or brazed to get acceptable heat transfer.

RE: Best thermally conductive paste for galvanized steel heat sink?

(OP)
Compositepro, 'radiator' may have been poor word choice, it was used here in
the sense of a car radiator, conducting heat exchange between air and water.

It's not a radiator in the sense of radiant heat, reflectance or emissivty.

I'm only interested here in enhancing the conductive heat exchange.

RE: Best thermally conductive paste for galvanized steel heat sink?

(OP)
Thanks, IRstuff, been reading up on it...

RE: Best thermally conductive paste for galvanized steel heat sink?

Soldering might make a better joint than epoxy.

RE: Best thermally conductive paste for galvanized steel heat sink?

Braze with a high-silver filler on bare steel parts.

Galvanize the assembly afterwards.

RE: Best thermally conductive paste for galvanized steel heat sink?

(OP)
btrueblood and MintJulep, I would solder or braze if I could, I know that's better,
but for cost restriction issues and a dozen other moving parts needing attention in
this project, I've had to compromise here and settle for less than best efficiencies.

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


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close