Is Immersion Copper Plating Real?

A. Hi, Annie. Sorry, but you are on the wrong track on this one. Of course immersion copper plating onto steel is real. Not only has it been demonstrated thousands of times, but it is used as an industrial process for materials such as welding rod. In simpler times it was even used as a wastewater treatment technology, with scrap autos placed in rural streams to remove copper from the water. And, of course, batteries would not work if the phenomenon were not real.

Conventional electrolytic copper plating is widely practiced on steel -- in fact chrome truck bumpers are steel, and often copper plated before the nickel and chrome plating.

Regards,

A. Copper does indeed immersion plate onto steel in acid ( but not alkaline) solutions. This is a chemical displacement reaction where the driving force is the dissolution of iron and one atom of copper replaces one atom of iron.

This is often called cementation in the metallurgical field, and the copper is not very adherent to the steel.

It is actually very easy to electroplate copper onto steel with good adhesion and good mechanical properties. To do this however, the first layer of copper is usually plated from an alkaline copper "strike" bath. After the first coating, either acid or alkaline copper baths can be used to plate a thicker deposit.

LK

A. Hello again, Annie.

Some of your statements are correct, but you are not viewing the copper plating of iron nails experiment correctly.

You are right that, if you had a sheet of steel and a sheet of copper pressed together and exposed to the elements, the steel sheet would rust and the contact with the copper sheet would be responsible for accelerating that rusting because the steel "wants" to dissolve and the more noble copper "wants" to stay undissolved. Similarly, if the experiment involved wrapping a copper wire around the nail and putting it in a bowl of water or salt water, the nail would rust for the same reason.

But the experiment is not about that. The experiment involves putting an iron nail into a solution of copper sulphate, which is a solution that already has a lot of copper dissolved into it. That dissolved copper wants to come out of solution and return to metallic form. And that's what it does. The positively charged Cu⁺⁺ ions in the copper sulphate ⇦this on eBay or Amazon [affil links] come into contact with the neutral Fe⁰ atoms and steal their electrons; the Cu⁺⁺ ions are reduced to Cu⁰ metal and the Fe⁰ atoms become Fe⁺⁺ ions dissolved in the solution.

Regards,