I think you're treading on thin ice when you start getting into anything over 62 rockwell in a knife blade, {CPM} is Crucible Powdered metal, its strong points are with a lack of grain during production you avoid any chance of warpage when you machine through the grains like a hot or cold rolled steel, but when you start getting 63 and or above the same lack of grain structure leads to brittleness and increased chance of breakage. 60/62 is plenty hard, yet far more durable. In my mind any how.

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