Alleima® 21-6-9 is an austenitic grade with a high level of Mn, a low level of Ni, and the addition of N. The grade is characterized by:
- High mechanical strength in the hard condition
- Very good impact toughness in temperatures down to -230°C (-382°F)
- Very good high temperature oxidation resistance
Standards
- UNS: S21900
Product standards
- AMS 5561
Customer specifications on request.
Chemical composition (nominal)
| C | Si | Mn | P | S | Cr | Ni | Mo | Cu | N |
|---|---|---|---|---|---|---|---|---|---|
| ≤0.040 | ≤1.00 | 8.00 - 10.00 | ≤0.030 | ≤0.030 | 19.00 - 21.50 | 5.50 - 7.50 | ≤0.75 | ≤0.75 | 0.15 - 0.40 |
Applications
Alleima® 21-6-9 seamless tube is used for components in the aircraft industry.
Forms of supply
Alleima® 21-6-9 seamless stainless steel tubes are supplied in the bright annealed condition or cold-worked.
| Outside diameter, mm (in.) | Wall thickness, mm (in.) |
|---|---|
| 2 - 65 (0.079 - 2.56) | 0.3 - 25 (0.012 - 1.0) |
| Outside diameter, mm (in.) | Wall thickness, % |
|---|---|
| +/- 0.05, or 0.1 (+/- 0.002, or 0.004) | +/- 10 |
| For special tolerance requirements, please contact Alleima. | |
Mechanical properties
| Proof strength, Rp0.2 | Tensile strength, Rm | Elongation, A2" |
|---|---|---|
| MPa (ksi) | MPa (ksi) | % |
| ≥330 (48) | ≥655 (95) |
≥35 |
| Proof strength, Rp0.2 | Tensile strength, Rm | Elongation, A2" |
|---|---|---|
| MPa (ksi) | MPa (ksi) | % |
| ≥827 (120) | ≥979 (142) | ≥20 |
Physical properties
Density
7.81 g/cm3 (0.282 lb/in3)
| Temperature, °C | J/(kg °C) | Temperature, °F | Btu/(lb °F) |
|---|---|---|---|
| 0 | 480 | 32 | 0.12 |
| 100 | 480 | 212 | 0.12 |
| Temperature, °C | MPa | Temperature, °F | ksi |
|---|---|---|---|
| 20 | 200 | 68 | 28.9 |
Poisson's ratio
0.285
Disclaimer: Recommendations are for guidance only, and the suitability of a material for a specific application can be confirmed only when we know the actual service conditions. Continuous development may necessitate changes in technical data without notice. This datasheet is only valid for Alleima materials.