High Speed Steels M42


DIN 1.3247 / M42 is a Cobalt-Molybdenum high speed steel according to DIN standard. The 1.3247 steel can reach high hardness of 70HRC after Quenching and Tempering. 1.3247 tool steel has good red hardness and high temperature hardness. Cutting tools made of 1.3247 steel can be used to cut high temperature iron base and casting alloys. This steel has poor toughness,so the quenching temperature should be low.

Chemical Composition



M42BM421.3247SKH59AFNOR Z85WDCV06-05-04-02


  1. High wear resistance
  2. High red hardness
  3. High toughness
  4. As a result of its low vanadium content, this grade exhibits good grindability.
  5. Fine Grain Size and Carbide Particle Size


  1. Die Sinking Cutters
  2. Milling Cutters
  3. Engraving Machines
  4. Tool Bits
  5. Cold Extrusion Rams
  6. Hobs
  7. Precision Broach
  8. Lathe Tools

    Heat Treatment

    1st Heating °C2nd and 3rd Hardening1 °C Quenching Tempering °C Hardness after pre-heating °C pre-heating °C tempering HRC
    up to approx. 400 in an air-circulating furnacea) 8501160-1190a) Saltbath, 550 Cat least three times 530-56066-69
    b) 850 and 1050b)Oil
    c) Air