Mat.No. 1.2379, DIN X155CrVMo12-1, AISI D2

PRINCIPAL DESIGN FEATURES
This alloy is one of the Cold Work, high carbon, high chromium type tool steels. D2 is a deep hardening, highly wear resistant alloy. It hardens upon air cooling so as to have minimum distortion after heat treatment.

APPLICATIONS
Used for long run tooling applications where wear resistance is important, such as blanking or forming dies and thread rolling dies.

MACHINABILITY
Machinability of D2 is poor. Using the water hardening simple alloy tool steels (W group) as a base of 100% the D2 alloy would rate about 50% in machinability.

FORMING
Forming is done by forging and machining.

WELDING
Consult the alloy supplier for information as to welding.

HEAT TREATMENT
Preheat very slowly to 1500 F and then increase temperature to 1850 F. Hold at 1850 F for 20 to 45 minutes and air cool (air quench).

FORGING
Forging may be done in the range of 1950 F down to 1750 F. Do not forge below 1700 F.

HOT WORKING
No data other than for “Forging”. Consult the alloy supplier for more information.

COLD WORKING
Cold working by conventional methods may be done with the alloy in the annealed condition.

ANNEALING
Anneal at 1600 F to 1650 F followed by slow furnace cooling at 40 F per hour or less.

AGING
Not applicable to this alloy.

TEMPERING
Tempering may be done in the range of 400 F for Rockwell C 61 to 1000 F for Rockwell C 54.

HARDENING
See “Heat Treatment” and “Tempering”.

OTHER COMMENTS
D2 is very high in wear resistance, but is also low in toughness.

Density: 0.283

Specific Gravity: 7.8

Melting Point: 2590

MoETensile: 28