M2 High Speed Tool Steel for Knife Blades
AISI M2 Tool Steel
Manufacturer: Various (CPM-M2 only by Crucible)
M2 is a high-speed tools steel enriched with Molybdenum, designed for high-wear cutting tools. M2 is typically hardened to RC 60-62 in production knives, though it can be hardened much more to RC 66-67. Benchmade is one of the major production knife companies using M2 steel in their knives, and earlier knives were marketed as HSS, short for High Speed Steel. Recently, Benchmade has began marketing knives with higher specification M4 High Speed Steel, which is M2's bigger brother.
M2 steel is very unique in its composition containing large amounts of Molybdenum and Tungsten in the mix, but the results is a very fine grained steel that makes a very hard and wear resistant blade steel. The small amount of chromium also gives this still a slightly better corrosion resistance than many other tool steels. Compared with other tool steels M2 has a poor toughness rating, though in practice, reports of toughness compared with premium stainless steels such as 154CM show M2 to be superior.
CPM-M2
CPM M2 is Crucible's M2 steel created with their proprietary particle metallury process. The CPM process boasts smaller, more uniform grain structures in the resulting steel.
Composition
| C | Cu | Cr | Mn | Mo | Ni | P | Si | W | V | S |
| 0.78-1.05 | 0.25 | 3.75-4.5 | 0.15-0.4 | 4.5-5.5 | 0.3 | 0.03 | 0.2-0.45 | 5.5-6.75 | 1.75-2.2 | 0.03 |