Resurfaced lifters
Novice question here. Dealing mostly with firearms….what about heat treating for hardness and using a process like black nitride or DLC for hardness and decreased wear? Black nitrided barrel
Bores have proven well for high volume high velocity projectiles.
Nitride is mostly hype. If not for the EPA, no one would nitride barrels.
With regard to a lifter, nitride is too thin. Typically being .0004-.0012 max. Dlc is an order of magnitude thinner.
Nitride happens well above 1000 degrees, and so parts can and do warp. The thin shell doesn't leave enough meat to grind after heat treat the way a true case hardening does. Through hardening a lifter is asking for cracks or fatigue failure.
Dlc can work, but with soft substrates it's like using an m&m as a bearing. If the base material is hard enough, then you don't benefit from the Dlc. Mostly Dlc is used for corrosion protection and wear resistance for things like seals and wipers (think hydraulic rams and the like). It's also widely used on cutting tools, but those things are already made from woodpecker lips.
I'm willing to bet the majority of cam/lifter failures are due to lifters not spinning in their bores. Either due to an improper face geometry, or improper lobe taper, or bore prep. All three things can be inspected by the assembler, but rarely are.
