The GE /GM locomotives (not Detroit Diesel) origninaly called for chrome liners with cast piston rings. The theory was that this created lower cost overhauls because most initial overhaul cycles would just require new rings, not cylinder removal and reconditioning.
A chrome surface was the medium of choice because when hard chrome is plated (not decorative chrome) the chromium 6 (yes of Erin Brockovich (sp?) fame) is laid down at very high current densities. This produces high molecular stresses in the deposit being laid down. This stress builds up until it creates a small fracture in the chrome deposit. Under a microscope, the surface looks like a dried up mud puddle. The lining is build up with layers of cracks upon layers of cracks. These micro cracks effectively create the porous surface which retains oil. Being chrome, the surface gradually wears but rather than becoming completely smooth, removal of chrome keeps on exposing more micro voids which keeps on creating the beneficial oil retention pockets. Once the chrome had been applied, the surface was honed using diamond surfaced stones and the diameter was expanded slightly (called a Mae West) around the ports to supposedly reduce ring pressure due to reduced supporting area.
The problem ended up being the eviromental concerns around hard chrome plating. (3000 gal tanks of chromic acid at 130'F with sulphuric and hydrofluoric acid as catalysts) Between emissions controls, spent solution disposal challenges and employee health concerns, an alternative solution had to be found and thats when the shift was made to cast liner/chrome rings. unfortunetly, when a cast surface wears, the beneficial oil retaining nature of the cross hatch lessens and lessens, thereby accelerating wear rates.
We also used spray welding to build up worn external location surfaces but we never achieved the bond strength we were really looking for.