Designation by Standards
| Steel No. | DIN | EN | AISI |
| 1.4903 | - | X10CrMoVNb9-1 | A213/P91 |
Chemical Composition (in weight %)
| C | Si | Mn | Cr | Mo | Ni | V | W | Others |
| 0.10 | 0.35 | 0.45 | 9.00 | 1.00 | - | 0.20 | - | - |
Description
1.4903 steel is creep-resistant material that is generally used for temperatures up to 630oC.
Applications
Boiler tube sector and for superheated steam fittings.
Physical properties (avarage values) at ambient temperature
Modulus of elasticity [103 x N/mm2]: 218, 207(200oC), 190(400oC), 162(650oC)
Density [g/cm3]: 7.7
Thermal conductivity [W/m.K]: 29.2
Specific heat capacity[J/g.K]: 0.46
Coefficient of Linear Thermal Expansion 10-6 oC-1
| 20-200oC | 20-400oC | 20-650oC |
| 11.3 | 12.0 | 12.7 |
Annealing
Heat to 730-780oC, cool slowly in furnace or air. Structure is martensite.
Hardening
Harden from a temperature of 1040-1090oC followed by air or oil quenching.
Mechanical properties at ambient temperature
Condition: Normalised and annealed, for size <"130 mm
0.2 % proof stress: 450 N/mm2
Tensile strength: 630-730 N/mm2
Elongation: 19% (Longit.), 17% (Transv.)
Notch impact energy (ISO-V): 40J (Longit.), 27J (Transv.)
0.2 % proof stress in N/mm2 vs. Temperature in oC
| 100oC | 150oC | 200oC | 250oC | 300oC | 350oC | 400oC | 450oC | 500oC | 550oC | 600oC |
| 410 | 395 | 380 | 370 | 360 | 350 | 340 | 320 | 300 | 270 | 215 |
Approximate values for creep rupture strength
Mean Creep Rupture Strength in N/mm2 vs. Temperature in oC
| Hours | 500oC | 520oC | 540oC | 560oC | 580oC | 600oC | 620oC | 640oC | 660oC |
| 10 000 | 289 | 252 | 216 | 182 | 151 | 123 | 99 | 79 | 62 |
| 100 000 | 258 | 220 | 183 | 150 | 120 | 94 | 73 | 56 | 42 |
| 200 000 | 246 | 208 | 171 | 139 | 110 | 86 | 65 | 49 | 35 |
Forging
Hot forming temperature: 1100-800oC, cool slowly. Note: Quenching and tempering treatment must always be carried out after hot forming.
Machinability
Metal-cutting machinning is the sae as for speial engineering steel gardes of corresponding strength.
Welding
The material displays good weldability. Welding must be followed by stress relief annealing with slow cooling. Filler material is MTS 3 or Thermanit from Thyssen.
Remark
All technical information is for reference only.