Are there any considerations which prevent use of a spray-on
lubricant? If you cannot use conventional lubricants, then I have 2 alternatives:
One approach would be to have the hard anodize (unsealed) impregnated/coated with a PTFE-containing dryfilm lubricant.
There are 3 grades, from simple dip + air dry to a baked on coating with phenolic (or other thermosetting resin) binder.
See MIL-A-63576A, which can be downloaded from the DoD's ASSIST site:
Another approach would be electroless nickel containing co-deposited PTFE particles:
"Composite Coatings: These types of coatings are specifically designed to enhance or improve the wear resistance properties for numerous applications. Co-deposits are chosen for frictional wear conditions and also heavy load wear conditions. Depending upon the type of co-deposit, composite coatings offer a wide variety of options for meeting specific demands.
Niklad Nilon: A unique Teflon dispersion blend that provides a 18 to 26 % v/v nickel Teflon co-deposit. The system produces the highest Teflon co-deposit, which is favored for frictional, low load wear environments.
Elnic 121 TF: A Teflon dispersion blend that provides a 10 to 20 % v/v nickel Teflon co-deposit. The advantage of lower Teflon co-deposits is the excellent coating performance under frictional wear and heavier loads. This condition is more representative in most applications today.
Niklad Dispersant: Utilized to enhance the co-deposition of diamonds, boron nitride, silicon carbide or other similar particles into an electroless nickel phosphorus deposit matrix."
The above info is from MacDermid;
other EN suppliers like Atotech have similar products.