M-4
Chemical Composition

Carbon              1.45%
Silicon              0.40%
Manganese        0.40%
Vanadium         4.00%
Chromium         4.50%
Molybdenum      4.50%
Tungsten          5.50%

Properties
M-4 is typically bought to meet chemistry requirements rather than physical requirements. For that reason, physical properties are generally not provided unless requested prior to production. Any material can be sent to a third party after production to be tested for physical properties.
Typical Uses
Blades
Broaches
Gear Hobs
Thread Rolls
Milling Cutters
Shaper Cutters
Shaving Cutters
Taps
Knives
Punches
Dies

M4

AISI M4 - a super high-speed steel having a very high carbon and vanadium content for exceptional abrasion resistance. It is well suited for premium-cutting tools of all types, and particularly those used for machining abrasive alloys, castings and heat-treated materials.

About AISI M4 (PM)

M4 PM, a member of the molybdenum-tungsten family of high-speed steels, is a special purpose grade which utilizes its higher carbon and vanadium contents to develop excellent abrasion resistance. Produced conventionally, M4 is difficult to machine in the annealed condition and grind in the hardened condition. M4 PM is produced by the powder metallurgy process and allows an addition of .06/.08 sulfur which provides a uniform dispersion of small sulfides throughout the structure and enhances machinability. Coupled with finer carbides and structural uniformity, better grindability is also achieved. These factors, along with increased toughness, are ideally suited for heavy-duty cold-work applications.