Bethlehem 66HS Knife Steel
Composition Analysis Graph, Equivalents And Overview

66HS(Bethlehem) - High-speed tool steel, has been around for a while. Popular choice for custom knives and high end and limited edition production knives as well. Gerber was using it as far back as in 90s. As a high speed tool steel M2 can hold its temper even at very high temperatures, and as such is used in industry for high-heat cutting jobs such as drill bits and other metal cutting instruments. None of that is what conventional knives are designed for, but as far as conventional knives are concerned M2 does have better wear resistance and toughness at the same hardness compared to such a popular knife steel as AISI D2. M2 makes better a blade steel, unless stain resistance is an issue. Benchmade used M2 in several knives, including AFCK, 710 HSS McHenry And Williams, Nimravus HSS, Ares, etc. As usual production knives are around 60-62HRC, but it's not really the optimum, at least not if you are aiming for best cutting efficiency and edge retention. 64 HRC M2 blades I have used were a lot better compared to those at 60HRC. At lower hardness M2 could be used for medium/large knives for heavy duty works I supose, but why bother, there are better choices for those tasks e.g. CPM 3V. For thin, high performance cutters, high hardness M2 works very well. Although, staring circa 2005 it gets replaced with AISI M4 high speed tool steel, which can be a bit harder, but more importantly has better toughness at the same hardness, which means better edge holding ability.

Manufacturing Technology - Ingot

Country - United States(US)

NOTE - Approximate composition based on manufacturer's or standard reference information and other alloys in the same reference group is shown.

^* - Listed as an equivalent or replacement for alloys in this group.