Designation
DIN: | X 40 Cr 14
|
AFNOR: | Z 40 C 14
|
UNI: | - |
AISI: | 420 / 420 ESR
|
Chemical composition:
Strength:
max. 240 HB
(≈ max. 800 N/mm²)
Thermal conductivity at 100 °C:
18 W/m K
Character:
low corrosion, high-alloy, low warpage steel for through hardening with excellent properties for mirror polishing as well as good photoetching, good machinability, high wear resistance and high dimensional stability
Application:
mould plates and inserts for working with chemically aggressive plastics; because of excellent polishing, suitable for optical and medical products
Treatment by
Polishing:
can be polished in the annealed and hardened state; good preliminary surface preparation work is decisive for a good polish
Etching:
good photoetching (graining)
EDM:
in the hardened and tempered condition, treat again for stress relief about 20°C below the last temperature
unusual:
Nitriding, hard chroming
Heat treatment:
Soft annealing:
750 to 800°C for about 2 to 5 hours
slow controlled cooling of 10 to 20°C per hour to about 650°C; further cooling in air, max. 200 HB
Hardening:
1000°C to 1050°C
15 to 30 minutes keeping curing temperature
quenching in oil/compressed gas/hot bath
obtainable hardness: 53 - 56 HRC
Tempering:
slow heating to tempering temperature immediately after hardening;
minimum time in furnace: 2 hours per 20 mm part thickness;
Tempering twice is recommended.
Annealing graph:
Technical tip
- Cold-work steel
- must be tempered several times after hardening (max. 52HRC). The demand for “max. hardness” often ends up in material breakage.
- mould temperature max. 200°C
- corrosion-resistant after hardening
- The ESR quality guarantees an extremely pure and homogeneous microstructure.
Vers l’aperçu de la construction de moules
Vers l’aperçu de la construction d'outils de découpe