1.4903
Data sheet material 1.4903 / AISI F91
X10CrMoVNb9-1
Martensitic high-temperature steel
Brief description
The material 1.4903 is a high-temperature martensitic steel. It has good mechanical properties (yield strength and creep rupture strength) under long-term conditions at temperatures above 500°C. In continuous operation, however, the maximum operating temperature should not exceed 650°C.
Standards and nomenclature
| EN | |
|---|---|
| DIN | X10CrMoVNb9-1 |
| AISI | F91 |
| US | K90901 |
| EN | |
|---|---|
| DIN | X10CrMoVNb9-1 |
| AISI | F91 |
| US | K90901 |
Chemical composition
| C (carbon) | 0,08 | 0,12 |
| Mn (manganese) | 0,3 | 0,6 |
| Si (silicon) | - | 0,5 |
| P (phosphorus) | - | 0,025 |
| S (sulphur) | - | 0,015 |
| Cr (chromium) | 8,0 | 9,5 |
| Ni (nickel) | - | 0,4 |
| Mo (molybdenum) | 0,85 | 1,05 |
| N (nitrogen) | 0,03 | 0,07 |
| Nb (niobium) | 0,06 | 0,1 |
| Al (aluminium) | - | 0,04 |
| V (vanadium) | 0,18 | 0,25 |
-
-
min.
max.
C
(carbon)
0,08
0,12
Mn
(Manganese)
0,3
0,6
Si
(Silicon)
-
0,5
P
(phosphorus)
-
0,025
S
(sulphur)
-
0,015
Cr
(chrome)
8,0
9,5
-
-
min.
max.
Ni
(nickel)
-
0,4
Mo
(Molybdenum)
0,85
1,05
N
(Nitrogen)
0,03
0,07
Nb
(niobium)
0,06
0,1
Al
(aluminium)
-
0,04
V
(Vanadium)
0,18
0,25
General properties
| Corrosion resistance | |
|---|---|
| Mechanical properties | medium |
| Forgeability | good |
| Weldability | good |
| Machinability | good |
Special properties
Can be used at temperatures up to 650°C
Corrosion resistance
Due to its low chromium content, the material 1.4903 has poorer corrosion resistance compared to other high-temperature steels.
Mechanical properties
at 20°C
Yield point
Rp0,2
N / mm²
≥ 450
Tensile strength
Rm
N / mm²
630 - 730
Elongation
A5,65
≥ 19%
Modulus of elasticity
kN / mm²
217
Forgeability
During the forging process, heating to 1050°C - 1100°C takes place first. Forging takes place in a temperature range of 1100°C - 850°C. After welding, renewed tempering at temperatures of 740°C - 770°C is recommended.
Weldability
The material 1.4903 can be welded using all processes except gas fusion welding. The material should be preheated to approx. 150°C before welding. The temperature of the intermediate layers should not fall below 350°C. After welding, stress relief annealing in the temperature range of 740°C - 770°C is recommended. The workpiece should then be cooled down slowly.
Machinability
The machinability is similar to that of comparable corrosion-resistant 121TP3 chromium steels.
Markets & Applications
Apparatus engineering
Pressure vessel
Steam boiler
Nuclear technology
Physical properties
at 20°C
Density
kg/dm³
7,7
Electrical
Resistance
(ohm) mm²/m
0,50
Magnetisability
available
Thermal conductivity
W/m K
26
Specific
Heat capacity
J/kg K
430
Processing
| Open-die and closed-die forging | |
|---|---|
| Machining | good |
| Automated processing | conditional |
Thermal treatment
| Hot forming | |
|---|---|
| Remuneration (+QT) | |
| Hardening | 1040 - 1090°C (cooling: oil, polymer, air) |
| Tempering | 730 - 780°C (cooling: oven, air) |
| Hot forming | |
|---|---|
| Remuneration (+QT) | |
| Hardening | 1040 - 1090°C (cooling: oil, polymer, air) |
| Tempering | 730 - 780°C (cooling: oven, air) |
Frequently asked questions
Important note
TEAM EDELSTAHL operates purely as a trading company without technical staff. Consequently, we are not authorised to provide material consulting services.
The above values and information on the properties and/or usability of the material are purely informative. This information is based on the experience of the manufacturer and TEAM EDELSTAHL. All information is without guarantee. Misprints, errors and changes excepted.
