Corrosion at Aluminum/Steel Junction

On Mon, 19 Jun 2006 18:34:46 +0000, Front Office
wrote:

I need to build a dozen outdoor canopies for an office building.
I want to use structural aluminum channel, bolted with steel bolts.

Where might expect corrosion to arise over the years, and would
it be mainly in the aluminum or in the steel bolts?

Thanks for any help.

Please post here or email me at grayscale[AT]verizon.net

Ralph

a product called Duralac is designed to prevent the electrolytic
corrosion between dissimilar metals.
it is an aviation product made in england. comes in a white and yellow
tube.
it is a toothpaste consistency yellow fluid containing zinc chromate.
it dries slowly to a rubber consistency.

the stuff is used for pop rivets with great benefit in corrosion
control. you just dip them in it prior to setting the pop in a wing
skin.

it is good stuff. two tubes in my aviation tool box.
Stealth Pilot

On Tue, 20 Jun 2006 22:05:55 +0800, Stealth Pilot
wrote:

a product called Duralac is designed to prevent the electrolytic
corrosion between dissimilar metals.
it is an aviation product made in england. comes in a white and yellow
tube.
it is a toothpaste consistency yellow fluid containing zinc chromate.
it dries slowly to a rubber consistency.

Minor point, it only contains Barium Chromate and White Spirit.

You can also buy bigger tins of it, It's used in a lot of marine
applications as well as aviation.


--

On Wed, 21 Jun 2006 00:41:07 +0100, Martin Evans
wrote:

On Tue, 20 Jun 2006 22:05:55 +0800, Stealth Pilot
wrote:

a product called Duralac is designed to prevent the electrolytic
corrosion between dissimilar metals.
it is an aviation product made in england. comes in a white and yellow
tube.
it is a toothpaste consistency yellow fluid containing zinc chromate.
it dries slowly to a rubber consistency.

Minor point, it only contains Barium Chromate and White Spirit.

You can also buy bigger tins of it, It's used in a lot of marine
applications as well as aviation.

had to drag out my tube.
that's true.

Stealth Pilot

Stealth Pilot wrote:
On Wed, 21 Jun 2006 00:41:07 +0100, Martin Evans
wrote:

On Tue, 20 Jun 2006 22:05:55 +0800, Stealth Pilot
wrote:

a product called Duralac is designed to prevent the electrolytic
corrosion between dissimilar metals.
it is an aviation product made in england. comes in a white and yellow
tube.
it is a toothpaste consistency yellow fluid containing zinc chromate.
it dries slowly to a rubber consistency.

Minor point, it only contains Barium Chromate and White Spirit.

You can also buy bigger tins of it, It's used in a lot of marine
applications as well as aviation.

had to drag out my tube.
that's true.

Stealth Pilot

Hard to get zinc chromate in the average consumer product
anymore. It's been linked to cancer. Zinc *oxide* is often seen in
those green aerosol primers now. I can still get Endura epoxy zinc
chromate, clearly labelled "for industrial use only."

Dan

wrote:
Stealth Pilot wrote:
On Wed, 21 Jun 2006 00:41:07 +0100, Martin Evans
wrote:

On Tue, 20 Jun 2006 22:05:55 +0800, Stealth Pilot
wrote:

a product called Duralac is designed to prevent the electrolytic
corrosion between dissimilar metals.
it is an aviation product made in england. comes in a white and yellow
tube.
it is a toothpaste consistency yellow fluid containing zinc chromate.
it dries slowly to a rubber consistency.

Minor point, it only contains Barium Chromate and White Spirit.

You can also buy bigger tins of it, It's used in a lot of marine
applications as well as aviation.

had to drag out my tube.
that's true.

Stealth Pilot

Hard to get zinc chromate in the average consumer product
anymore. It's been linked to cancer. Zinc *oxide* is often seen in
those green aerosol primers now. I can still get Endura epoxy zinc
chromate, clearly labelled "for industrial use only."

Either go talk to a window maker or for information as to
bolts/connectors compatable with aluminium go to
http://www.everything-stainless-stee...eel-fasteners/

In message .com,
writes
Hard to get zinc chromate in the average consumer product
anymore. It's been linked to cancer.

Milspec products a decade ago used to use strontium chromate in a grease
base, but even then the search was on for a less unfriendly replacement.

--
Paul J. Adam