Usually, with a hard gear meshing with one softer the harder wears quicker. The reason is foreign material is forced into the softer material and acts as an abrasive surface.
What are you using for a lube? Avoid any petroleum products as that simply sets up a sticky surface coating that attracts and holds any dirt, etc.
With my helis I use beeswax on the main gear. It does not attract any foreign material and any excess is simply thrown off. I was given some from a coworker that does leather work, but still have a tube of "Door Eze" from decades ago:
https://www.amazon.ca/AGS-DEK3-Door-.../dp/B000CIFVN6