system
Given the following post, respond as if you're commenting on Reddit:
human
Iridium and similarly hard metals are difficult to machine due to extreme work hardening. Is "grinding" based machining also affected?

I understand how drilling and traditional milling would be made essentially impossible due to rapid work hardening, but couldn't a "grinding" approach be used to get around this? 


Is there something I am not understanding about work hardening? Does work hardening affect materials at such a "small-scale" as sanding away tiny pieces of the material?
gpt
Iridium can be machined, it's just a lot harder to do than other materials and there are much eaisier ways to form it. If you want to cut it with an endmill you are going to want a properly coated tool that has a hard coating capable of handling high temperatures - depending on your setup you might be able to do it with PCD or AlTiN tool. Most machinists would get pretty pissy if you tried to get them to run the job though, the tools just won't last that long and it will take a lot of babying, you might have to swap tools regularly before failure in the middle of a job, use very low speed/feeds, etc.

You can grind it, that's not a problem. Best way to cut it is probably EDM. Milling is only the "worst" option, not impossible. BTW grinding is not an ideal solution because the grinding tool will wear over time and it is hard to hold tolerances. Grinding can be done very precisely but will often use in-situ measuring machines to machine-measure the surface, which is costly but for example one of the best ways to form a complex lens.