Carpenter Three Star Knife Steel
Composition Analysis Graph, Equivalents And Overview

Three Star(Carpenter) - High speed tool steel. By composition and characteristics it is somewhere in between AISI M2 and AISI M4 high speed tool steels. Both of those alloys are very popular choices for high end knives, M4 being a winner of many cutting competitions. M3 is more wear resistant and a bit tougher compared to M2, but M4 having more alloying content performs better in those departments, which is why M4 is more popular choice I suppose. Still, a very decent alloy on its own, and depending on heat treatment can be used in high performance cutters or more of a heavy duty knives as well. Generally speaking AISI standard doesn't contain M3 steel specification, it does have M3:1 and M3:2 alloy specs(M3 class 1 and class 2 respectively), but not M3. Still, foreign steel makers and dealers often use it as an AISI equivalent of their products.

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.