In article , Marshall Johnson
says...

Something's not right here. I knew it would be tough but not THAT
tough. How come the endmill wore out so quickly?

Post up the sfpm you were running on the tool,
and the feed rate. Either your idea of 'slow'
for the rpm is incorrect, or you were running
the feed rate so slow as to allow the material
to work harden under the tool.

Just a guess, there will be others here that
will be more accurate.

Jim

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