1.2738, 40CrMnNiMo8-6-4, AISI P20+Ni, 40CMND8 - plastic mould steel, data according to ISO 4957:2001
Table of content:
| Standard | Grade | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chemical composition % | |||||||||||||||
| C: | Si: | Mn: | P: | S: | Cr: | Mo: | Ni: | ||||||||
| ISO | 1.2738/40CrMnNiMo8-6-4 | ||||||||||||||
| 0.35 - 0.45 | 0.2 - 0.4 | 1.3- 1.6 | <0.03 | <0.03 | 1.8 - 2.1 | 0.15 - 0.25 | 0.9-1.2 | ||||||||
| GOST | 40Ch2GNM - 40X2ГHM | ||||||||||||||
| 0.35 - 0.45 | 0.2-0.4 | 1.3-1.6 | <0.035 | <0.035 | 1.8-2.1 | 0.15 - 0.25 | 0.9-1.2 | ||||||||
| ASTM | AISI P20+Ni | ||||||||||||||
| 0.4 | - | 1.5 | - | - | 1.9 | 0.2 | 1.0 | ||||||||
| NF | 40CMND8 | ||||||||||||||
| 0.4 | 0.3 | 1.5 | <0.012 | <0.005 | 1.9 | 0.2 | 1.0 | ||||||||
1.2738, 40CrMnNiMo8-6-4, AISI P20+Ni, 40CMND8 – description
1.2738 is a plastic mould tool steel, used mainly for plastic injection die moulds. It can be viewed as enhanced version of 1.2311 alloy, with 1% nickel content having a positive effect on hardenability.
The steel is machinable, polishable, and suitable for texturing. Welding is somewhat difficult, but possible. Make sure to pre-heat and perform tempering, when the piece colled down after welding.
Physical and mechanical properties
1.2738 - general physical and mechanical properties in ambient temperature:
- Linear expansion coefficient: 11.2 *10-6m/(m*K)
- Thermal conductivity: 35 W/(m*K)
- Hardness (in soft annealed condition): < 235 HB
- Hardness (in hardened and tempered condition): < 51 HRC
Linear expansion coefficient of 1.2738 steel, in high temperature and in hardened and tempered condition:
- Temperature range: 20-200 °C - 12.8 *10-6m/(m*K)
- Temperature range: 20-300 °C - 13.5 *10-6m/(m*K)
- Temperature range: 20-500 °C - 14.3 *10-6m/(m*K)
- Temperature range: 20-700 °C - 14.9 *10-6m/(m*K)
Thermal conductivity of 1.2738 steel, in high temperature and in hardened and tempered condition:
- Testing temperature: 350 °C - 34 W/(m*K)
- Testing temperature: 700 °C - 33 W/(m*K)
Hardness of steel 1.2738 in hardened and tempered condition, at various tempering temperatures:
- Tempering temperature: 100 °C - 51.5 HRC
- Tempering temperature: 200 °C - 50.2 HRC
- Tempering temperature: 300 °C - 48 HRC
- Tempering temperature: 400 °C - 46.2 HRC
- Tempering temperature: 500 °C - 43 HRC
- Tempering temperature: 600 °C - 39 HRC
- Tempering temperature: 700 °C - 29 HRC
Heat treatment and working
Recommended working and heat treatment parameters for 1.2738 alloy:
- Forging: 1050-850 °C
- Rolling: 1050-850 °C
- Quenching: 840-870 °C
- Soft annealing: 710-740 °C
We deliver this steel alloy as:
- Forgings
- Rods
Replacements, equivalents and other designations:
1.2738, 40CrMnNiMo8-6-4, AISI P20+Ni, 40CMND8, 40Ch2GNM, 40Х2ГНМ, M238