ThePipingMart Blog Grades M42 High Speed Steel – Composition, Properties, and Uses

M42 High Speed Steel – Composition, Properties, and Uses

Tool Steel M42

Tool steel M42 is a high-speed molybdenum steel with very good resistance to abrasion and wear. It’s often referred to as “super” steel because of its unique ability to maintain cutting edges for extended periods of time. The composition and properties of tool steel M42 make it an ideal material for many manufacturing applications, especially those that involve cutting, drilling, and grinding. Let’s take a closer look at the properties and uses of this versatile material.

M42 Tool Steel Composition

M42 HSS contains 8% chromium, 4% tungsten, 2% molybdenum, 0.7% vanadium, 0.5% cobalt, and 0.2% silicon. It also contains trace amounts of manganese, nickel, sulfur, and phosphorus. This combination of elements gives it excellent heat hardness and toughness without losing its hardening capacity in cold temperatures.

Element Content (%)
C 1.05-1.15
Mn 0.15-0.40
Si 0.15-0.65
Cr 3.50-4.25
Ni 0.3
Mo 9.00-10.00
W 1.15-1.85
V 0.95-1.35
Co 7.75-8.75
Cu 0.25
P 0.03
S 0.03

M42 Tool Steel Equivalent

  • AFNOR 07-05-04-04-02
  • DIN 1.3246
  • ASTM A600
  • FED QQ-T-590
  • UNS T11342
  • DIN 1.3247

M42 Tool Steel Chemical Properties

Steel M42 is a high-speed, molybdenum-based steel alloy that offers exceptional wear and abrasion resistance. A strong combination of carbon and tungsten content provides a workable hardness with excellent edge sharpness. Not surprisingly, this versatile steel is often used for cutting tools in metalworking and other applications requiring extreme durability. Its chemical composition also includes cobalt for added strength, vanadium for better workability, and chromium to prevent corrosion. With such unique properties, it’s little wonder tool steel M42 is an invaluable choice for many industries, from aerospace to medical engineering.

M42 Tool Steel Mechanical Properties

Tool Steel M42 offers superior strength due to its alloy content which provides higher carbon content compared to other tool steels. It has a Rockwell Hardness rating of 65 HRC (Rockwell scale) at room temperature, which increases after the heat treating process with higher hardness ratings up to 69 HRC depending on grade used for tooling application.

Mechanical Properties Metric Imperial
Hardness, Rockwell C (oil quenched from 1204°C, 5 minutes) 64.3 64.3
Hardness, Rockwell C (oil quenched from 1177°C, 5 minutes) 65.5 65.5
Hardness, Rockwell C(oil quenched from 1163°C) 65.8 65.8
Izod impact unnotched (oil quenched at 1191°C; 510°C temper temperature) 13.6 J 10.0 ft- lb
Izod impact unnotched (oil quenched at 1191°C; 622°C temper temperature) 24.4 J 24.4 J
Machinability (1% carbon steel) 35.0 – 40.0% 35.0 – 40.0%
Poisson’s ratio 0.27-0.30 0.27-0.30
Elastic modulus 190-210 GPa 27557-30457 ksi

M42 Tool Steel Physical Properties

Its physical properties include:

  • Density of 8 gm/cm³.
  • Melting point of 1450°C.
  • Thermal conductivity of 17 W/mK.
  • Electrical resistivity of 0.19 ohm-cm, and modulus of elasticity of 200 GPa.
Physical Properties Metric Imperial
Density 7.81 g/cm3 0.282 lb/in3

M42 Tool Steel Uses

Alloy M42 is an incredibly strong and resilient variety of high-speed steel that has had a wide range of industrial uses over the years. It is well known for its excellent red hardness and superior abrasion resistance, making it a good fit for metal cutting tools that would otherwise quickly be destroyed. This makes M42 perfect for use in metalworking industries, where it has been used to make important pieces like lathe tools, drill bits, milling cutters and other cutting tools, as well as saw blades. Additionally, it can be used in the production of gear wheels, turbine rotors and components like valves and cams due to its extreme tensile strength. With so many uses for one type of tool steel, it’s no wonder why M42 has become such a mainstay in the industry

Heat Treatment

Tool Steel M42 can be hardened through various heat treatment processes, such as quenching and tempering, to increase its strength and durability while maintaining its hardness level at 65 HRC for most applications. Other processes, such as double tempering or triple tempering, may be needed if higher levels are required up to 69 HRC.


Its machinability rate is 55-60 (on a 1-100 scale), making it suitable for high-speed machining operations such as drilling, tapping, reaming etc.

Resistance Characteristics

It has excellent wear resistance due to its high carbon content combined with its chromium content, helping reduce friction during operation, making it ideal for long-life tools or parts that are subject to frequent use or wear.

Corrosion Resistance

Its corrosion resistance is enhanced by adding chromium, which helps form protective oxide layers on the surface when exposed to moisture or other corrosive elements in the environment.


Tool Steel M42 is an incredibly versatile material used in many industrial applications due to its exceptional mechanical properties, chemical composition, corrosion resistance, heat resistance and high hardness level. From cutting tools to parts that need extra durability against abrasion or wear—tool steel m42 can provide them all! With careful heat treatment procedures combined with proper welding techniques—this super steel can help your business achieve excellence!

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