Just doing some general fettling on my car and I have an old tin of the Duralac sold by Eliseparts:
This just looks like paint and goes on quite thin with a paint brush although the website states “Simply smear a layer between any 2 surfaces not only will it arrest the corrosion process it will act as a very fine thread sealer and enable easy bolt/nut removal in the future.”
Looking on some of the boat websites they seem to offer this:
which looks more like a paste to be applied in a similar way to say copperslip.
Just lookig up the “active” ingredients - seems to be barium chromate.
Barium chromate is a fine light yellow powder with the formula BaCrO4.
There are a few uses of barium chromate:
As an oxidizer and/or burn rate modifier in some pyrotechnic compositions, especially delay compositions.
As a pigment in paints, ceramics, coloring glasses, fuses, and porcelains.
[color:#CC0000]As a corrosion inhibitor to prevent electrochemical corrosion at the joints of dissimilar metals.
[/color] In safety matches.
In metal primers.
In ignition control devices.
As an initiator for explosives.
but not sure why it’s better at this than say grease…
I was asking mainly because when I took of the engine mounts, subframe and the balljoint brackets on the uprights, there was still corrosion in there despite the duralac.