1.7131 steel for case-hardening

Designation

Chemical composition:

Strength:

max. 186 HB
(≈ max. 635 N/mm²)

Thermal conductivity at 20 °C:

44 W/m K

Character:

steel for case hardening for parts requiring a core strength of 800 –1100 N/mm² and high wear resistance

Application:

guiding elements, cores and machine parts with high surface hardness; synthetic resin press moulds for processing thermoplastics and thermosetting plastics

Treatment by

is possible:
Polishing, etching, EDM
Nitriding:
Usually, hardened parts are not nitrided → loss of hardness.
Hard chroming:
recommended, results in increased wear and corrosion resistance

Heat treatment:

Soft annealing:

670 to 710 °C for about 2 to 5 hours
slow controlled cooling, further cooling in air, max. 205 HB

Carburising:
900 to 950 °C. The choice of the carburising means and carburising temperature depends on the desired surface carbon content, the carburising graph and the required case depth.

Case hardening:
870 to 930 °C in powder/salt bath, cooling in oil/warm bath at 160 to 250 °C

Intermediate stress-relieving heat treatment:
630 to 650 °C, about 2 to 4 hours with slow furnace cooling

Preheating:
350 °C depending on dimensions

Hardening:
curing temperature 810 to 840 °C in oil of ~ 60 °C warmth

Cooling:
in to about 100 °C oil, then in air to about 50 °C

Tempering:
1 hour per 20 mm part thickness, min. 2 hours

Tempering:
150 °C - 200 °C

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