Calcium bentonite can be electroplated onto steel. After it is electroplated on to steel it has a rough and porous like surface that is very hard and tough.
If you were to electroplate a thin layer of calcium bentonite onto steel then brush on a thin coating of copper oxide. The copper oxide would stick to the surface and fill some voids because the calcium bentonite that was electroplated on to the steel is porous. Is it then possible to electroplate more calcium bentonite over top this copper oxide layer? And repeat the process so that you have layers that start with steel then calcium bentonite then copper oxide then calcium bentonite then copper oxide then calcium bentonite etc. The final layer could be smoothed out by sanding/grinding.
I know that most paint for boats use copper oxide to keep barnacles from forming but thot what if there were a more permanent or tougher/longer lasting solution to that problem that causes ships to waste massive amounts of fuel due to drag.