M42 / DIN 1.3247 / AISI M42 Steel Grade

Toolman Special Steels is proud to produce and offer M42 (1.3247) - a high speed cobalt alloy steel that is regularly manufactured. When compared to traditional high speed steel, it has outstanding thermal hardness so that it is suitable for higher cutting speeds or extends the time before the cutting tool needs replacement.

Steel Properties
  • Good high temperature hardness

  • High wear resistance

  • High cutting ability

  • High impact resistance

  • Fine and uniform grain size

  • Good grindability due to lower V - content.

Chemical Composition

Element Value
C 1.10
Cr 3.90
Mo 9.20
W 1.40
Co 7.80
V 1.20

Mechanical Properties

Property Value
Hardness (HBW) 269 max (Annealed)
Quenching and Tempering Hardness (HRC) 66 min

Physical Properties

Property Value
Density (g/cm³) 8.3

Modulus of Elasticity

Temperature (°C) kN/mm²
20 225

Thermal Properties

Temperature (℃) Thermal Expansion Coefficient (10^-6/℃)
500 12.4
600 12.5

Thermal Conductivity

Temperature (℃) Thermal Conductivity (W/m•K)
20 19

HEAT TREATMENT AND PROCESSES

Heat treatment

Process Details
Decarburization Use rectified salt baths or proper atmosphere control in furnace hardening to avoid decarburization.
Normalizing Not recommended.
Hardening Preheat at 1500/1600°F (816/871°C) thoroughly. Transfer to high heat of 2150/2200°F (1177/1204°C) in salt or 25°F (14°C) higher in atmosphere furnaces.Quench in salt at 1000/1150°F (538/621°C) until equalised, then cool in air. Alternatively, quench in warm oil. Cool to 150°F (66°C) max before tempering.
Deformation Size change is minimal during hardening. When hardened from 2175°F (1191°C) in salt, a 1" (25.4 mm) cube expands about 0.0005" (0.013 mm). Expands similarly when tempered at 1000°F (538°C).
Tempering Temper between 950°F (510°C) and 1100°F (593°C). Tempering below 1000°F (538°C) not recommended. Use triple temper cycle with a minimum of two hours at temperature each time. Cool to room temperature after each cycle.
Tempering °C HRC
200 62.5
300 61
400 61.5
500 66.5
520 68
560 67
600 64
650 50
700 42
Applications
  • Drills

  • Hobs

  • Taps

  • End mills

  • Milling cutters

  • Form and gear Cutters

  • Broaches and Chasers

  • Counterbores

  • Trimming Dies

Quality Assurance

Our M42 1.3247 steel undergoes rigorous testing and quality control to meet international standards, ensuring consistent performance and reliability. Certificates and test reports are available upon request. Feel free to reach out to us for more information on our M42 1.3247 steel products or to discuss your specific requirements. We're dedicated to providing top-quality steel solutions that meet your needs and exceed your expectations.

Manufacturing Range

ROUNDS SQUARES
SIZE (MM) CONDITION SIZE (MM) CONDITION
6.00 - 14.00 CG 7.2, 8.8, 10.5, 11 HRA
15.00 - 50.00 HRAP 13.5, 14, 17.5, 21 HRA
52.00 - 405.00 FAT 27, 32, 40 HRA
52.00 - 305.00 FA

Flats

THICKNESS WIDTH CONDITION
5.00 - 32.00 21.00 - 105.00 HRA
32.00 - 105.00 40.00 - 205.00 FA