1.2379 Steel for through hardening

Designation

Chemical composition:

Strength:

max. 255 HB
(≈ max. 860 N/mm²)

Thermal conductivity at 100 °C:

21 W/m K

Character:

high-alloy steel for through-hardening with moderate machinability; extremely wear resistant and low warpage, good dimensional stability, toughness and through hardenability

Application:

mould plates and inserts as well as wear plates and cutting dies with increased wear resistance

Treatment by

Polishing:
possible when hardened

Nitriding:
very well suited, due to the fact that the hardness of the base material will not fall below 60 HRC

EDM:
possible, Structure eroding not possible

Hard chroming:
possible

Etching:
not possible, coarse carbides are washed out

Heat treatment:

Soft annealing:
800 to 850 °C for about 2 to 5 hours; slow controlled cooling of 10 to 20 °C per hour to about 600 °C; further cooling in air, max. 235 HB

Hardening:

1020 °C
1060 to 1080 °C
quenching in oil/air/hot bath
obtainable hardness: 63−65 HRC

Tempering:
slow heating to tempering temperature (to avoid forming of cracks) immediately after hardening; triple tempering at max. secondary hardening temperature is recommended; rapid cooling following the tempering improves the dimensional stability; maximum hardness achievable after tempering: 60-62 HRC

Annealing graph:

Technical tip:

• secondary hardening, very good base material for nitriding or coating

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