UTOPNIN
  
Identification

 

Designation by Standards
Brand Name Ravne No. Mat. No. DIN EN AISI
UTOPNIN 249 1.2738 40CrMnNiMo8-6-4 - P20 Mod.

 

Chemical Composition

 

Chemical Composition in Weight %
C Si Mn Cr Mo Ni V W Others
0.40 0.30 1.45 1.95 0.20 1.05 - - -

 

General Information

Description
This steel is in the category generally labeled as Mold Steels. Nickel and chromium are the alloying elements for hardness and toughness. Cold work tool steel with good machinability, excellent polishability, suitable for texturing. Improved through hardenability comapred to Mat.No. 1.2311.

Applications
Typically used for relatively low temperature applications such as die casting dies and injection molds, synthetic plastic moulds dies, for large moulds.

 

Properties

Physical properties (avarage values) at ambient temperature:
Modulus of elasticity [103 x N/mm2]: 205
Density [g/cm3]: 7.80
Thermal conductivity [W/m.K]: 29.0
Specific heat capacity[J/g.K]: 0.46

Coefficient of Linear Thermal Expansion 10-6 oC-1
20-100 'C 20-200 'C 20-300 'C 20-400 'C 20-500 'C 20-600 'C 20-700 'C
11.7 12.3 13.0 13.3 13.7 13.7 14.0

Continuous Cooling Transformation (CCT) Diagram

 

Heat Treatment

Soft Annealing
Heat to 710-740 'C, cool slowly. This will produce a maximum Brinell hardness of 235.

Stress Relieving
Stress relieving to remove machining stresses should be carried out by heating to 650 'C, holding for one hour at heat, followed by air cooling. This operation is performed to reduce distortion during heat treatment.

Hardening
Harden from a temperature of 840-880 'C followed by oil, air ot warm bath (180-220 'C) quenching. Hardness after quenching is 52 HRC.

Tempering
Tempering temperature: See the data bellow.

Tempering Temperature ( 'C) vs. Hardness (HRC) vs. Tensile Stregth (N/mm2)
100 'C 200 'C 300 'C 400 'C 500 'C 600 'C 600 'C
52 51 49 46 42 36 28
1790 1730 1620 1480 1330 1140 920

Effect of Tempering Temperature on Hardness

 

Workability


Forging
Hot forming temperature: 1093-898 'C.

Machinability
Machinability is relatively good at about 80% that of the W group water hardening steels.