Heat Treating and Processing, Steel and Knife Properties

13 Myths about Heat Treating Knives

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General Heat Treating Myths

1. Heat Treating is the most important factor for high performance knives. This one started out along the lines of “even the best steel will perform poorly if given a bad heat treatment,” and that I can’t disagree with too much. However, it has become somewhat fashionable to talk about knife performance as entirely (or almost entirely) controlled by the knifemaker’s skill in heat treatment. This has some truth to it as knifemakers who use a subpar heat treatment will certainly have subpar performance. However, the heat treatment can only do so much. No heat treatment is capable of making high carbide CPM 15V into a high toughness steel. No heat treatment can turn 1095 carbon steel into a stainless. And I would argue that the single most important factor for knife performance is the edge geometry rather than the steel selection or heat treatment. The edge geometry greatly controls the cutting ability and edge retention of the knife and also resistance to chipping and rolling. The image below shows measured edge retention of 154CM knives with different edge angles so you can see the vast difference in measured performance (higher number means more cardstock cut). Of course, focusing on any one of these factors at the expense of the others: steel selection, heat treatment, and edge geometry, is a mistake and each should be optimized for the given knife. But if we were to pick one factor that is the “most important” I’m not sure that heat treatment would be the one. read more