Nitrated crank?
#2
Also known as case hardened. Very general, its heat treated, in an oven, often with a high nitrogen gas atmosphere, but it can be a powder coating etc. Nitriding leaves a thin surface coating that is hard and wear resistant, over a softer but tougher core.
#3
You can cryogenically treat the whole thing. Block, rings, rods, crank etc...
If you are going max effort or FI, it would be worth it, otherwise, overkill.
What cryo does is change Austenite (carbon particles) into Marsenite, which then makes the alloy extra strong.
One tip though, if you decide on something like that, make sure you file fit your rings before you treat them, otherwise it is a PIA afterwards.
No coating to wear off, no gimmick, just taking the alloy to another level.
If you are going max effort or FI, it would be worth it, otherwise, overkill.
What cryo does is change Austenite (carbon particles) into Marsenite, which then makes the alloy extra strong.
One tip though, if you decide on something like that, make sure you file fit your rings before you treat them, otherwise it is a PIA afterwards.
No coating to wear off, no gimmick, just taking the alloy to another level.