Corrosion Resistant Alloys
NAS NW276 (UNS N10276), comparable to Hastelloy® C-276 Alloy
Providing superior corrosion resistance in both oxidizing and reducing environments, NAS NW276, comparable to Hastelloy® C-276 alloy, is an exceptional alloy made of nickel, chromium and molybdenum. Carbide precipitation is suppressed in the heat-affected zone during welding due to the reduction of carbon and silicon content, further improving the corrosion resistance. These features make NAW NAS NW276 a popular alloy for use in materials subjected to severe environments such as found in chemical plants. Nippon Yakin supplies NAS NW276 in plate, sheet and strip forms.
Coil
Sheet
Plate
Designation / Standard
| Nippon Yakin Grade | ASTM B575 | DIN 17744 / 17750 | JIS H4551 |
|---|---|---|---|
| NAS NW276 | UNS N10276 | 2.4819 | NW 0276 |
Chemical Composition
NW 0276
| C | Si | Mn | P | S | Ni | Cr | Mo | Fe | Co | W | V | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Min | ― | ― | ― | ― | ― | ― | 14.5 | 15.0 | 4.0 | ― | 3.0 | ― |
| Max | 0.010 | 0.08 | 1.0 | 0.04 | 0.03 | Balance | 16.5 | 17.0 | 7.0 | 2.5 | 4.5 | 0.35 |
UNS N10276
| C | Si | Mn | P | S | Ni | Cr | Mo | Fe | Co | W | V | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Min | ― | ― | ― | ― | ― | ― | 14.5 | 15.0 | 4.0 | ― | 3.0 | ― |
| Max | 0.010 | 0.08 | 1.0 | 0.04 | 0.03 | Balance | 16.5 | 17.0 | 7.0 | 2.5 | 4.5 | 0.35 |
Physical Properties
| Specific heat (J/kg･K) | 436 | |
| Specific resistivity (μΩ･cm) | 130.0 | |
| Thermal conductivity (W/m･K) | 10.8 | |
| Thermal diffusivity (m²/s) | 2.8 x 10-6 | |
| Coefficient of thermal expansion (10-6/℃) | 20–100℃ | 12.2 |
| 20–200℃ | 12.5 | |
| 20–300℃ | 12.9 | |
| 20–400℃ | 13.2 | |
| 20–500℃ | 13.6 | |
| Young's modulus (MPa) | 21.1 x 104 | |
| Modulus of rigidity (MPa) | 80.8 x 104 | |
| Ferromagnetism | None | |
| Melting point (℃) | 1325-1369 | |
Mechanical Properties
NW0276
| 0.2% proof stress (N/mm2) |
Tensile strength (N/mm2) |
Elongation (%) |
Hardness (HRB) |
|---|---|---|---|
| ≥ 275 | ≥ 690 | ≥ 40 | ― |
UNS N10276
| 0.2% proof stress (N/mm2) |
Tensile strength (N/mm2) |
Elongation (%) |
Hardness (HRB) |
|---|---|---|---|
| ≥ 283 | ≥ 690 | ≥ 40 | ≤ (100) |
Examples
| 0.2% proof stress (N/mm2) |
Tensile strength (N/mm2) |
Elongation (%) |
Hardness (HRB) |
|
|---|---|---|---|---|
| Hot-rolled plate sheet, 14-mm thick |
372 | 763 | 71 | 83 |
| Cold-rolled sheet, 12-mm thick |
319 | 738 | 76 | 83 |
| Cold-rolled sheet, 2-mm thick |
366 | 785 | 61 | 86 |
Corrosion Resistance
Pitting Corrosion Resistance
| Alloy | Critical pitting corrosion temperature (CPT) | |
|---|---|---|
| 6%FeCl3 + 1%HCl solution (ASTM G48 Method C) |
Green death solution | |
| NAS NW276 | > 120℃ | > 120℃ |
| NAS 254N | 80℃ | 80℃ |
| NAS 329J3L | 50℃ | 45℃ |
| SUS 316L | 10℃ | 25℃ |
Crevice Corrosion Resistance
| Alloy | Critical pitting corrosion temperature (CCT) | |
|---|---|---|
| 6%FeCl3 + 1%HCl solution (ASTM G48 Method D) |
Green death solution | |
| NAS NW276 | 100℃ | 110℃ |
| NAS 254N | 40℃ | 45℃ |
| NAS 329J3L | 25℃ | 30℃ |
| SUS 316L | < 0℃ | < 0℃ |
Test conditions:
- 1) ASTM G48 Method C: Test duration 72h
- 2) ASTM G48 Method D: Test duration 72h, crevice formation by multicrevice
- 3) Immersion in green death solution: Test duration 24h, test solution 7%H2SO4 + 3%HCl + 1%FeCl3 + 1%CuCl2;multicrevice is used in the crevice corrosion test
Intergranular Corrosion Resistance
Test conditions:
ASTM G28 Method A
Test duration 24h in a boiling solution 50%H2SO4 - Fe2 (SO4)3 solution
Acid Resistance
| Test solution | Temperature (℃) |
Concentration (%) |
Corrosion rate (g/m²･hr) | |||
|---|---|---|---|---|---|---|
| NAS NW276 | NAS 254N* | NAS 329J3L* | SUS 316L | |||
| H2SO4 | 80 | 5 | 0.02 | 0.02 | 0.00 | 1.10 |
| 10 | 0.03 | 0.02 | 0.14 | 2.92 | ||
| 20 | 0.04 | 1.16 | 3.33 | 20.1 | ||
| 40 | 0.06 | 1.78 | 250.5 | 291.3 | ||
| 60 | 0.08 | 1.86 | 263.1 | 72.0 | ||
| 80 | 0.03 | 2.82 | 90.4 | 11.1 | ||
| Boiling | 5 | 0.10 | 1.43 | 0.61 | 5.45 | |
| 10 | 0.16 | 2.49 | 3.30 | 18.0 | ||
| 20 | 0.33 | 6.18 | 76.2 | 108.7 | ||
| 40 | 1.44 | 21.0 | 271.7 | 297.8 | ||
| HCl | 80 | 0.1 | 0.00 | 0.00 | 0.00 | 0.01 |
| 1.0 | 0.02 | 0.00 | 0.01 | 2.45 | ||
| 2.0 | 0.03 | 3.15 | 19.0 | 6.66 | ||
| 3.0 | 0.33 | 12.8 | 51.5 | 13.6 | ||
| Boiling | 0.1 | 0.00 | 0.00 | 0.00 | 0.01 | |
| 1.0 | 0.23 | 0.13 | 4.82 | 6.32 | ||
| 2.0 | 0.91 | 27.8 | 56.7 | 33.6 | ||
| 3.0 | 1.64 | 54.2 | 145.2 | 69.1 | ||
Test condition: Test duration 24h
Converted to mm/y from unit corrosion rate, g/m²･h
mm/y = g/m²･h x 8.76/d (d: density)
[d] NAS NW276: 8.90g/cm³, NAS 254N: 8.06g/cm³, NAS 329J3L: 7.80g/cm³, SUS 316L: 7.98g/cm³
* NAS 254N: 23Cr-25Ni-5.5Mo-0.2N (austenitic super stainless steel)
* NAS 329J3L: 22.5Cr-5.3Ni-3.2Mo-0.16N (duplex stainless steel)
Stress Corrosion Cracking Resistance
| Alloy | MgCl2 concentration [boiling points (℃) shown in parentheses] | |||||
|---|---|---|---|---|---|---|
| 20% (108) | 25% (110) | 30% (115) | 35% (126) | 38% (134) | 42% (142) | |
| NAS NW276 | ○ | ○ | ○ | ○ | ○ | ○ |
| NAS 254N | ○ | ○ | ○ | ○ | ○ | ○ |
| NAS 329J3L | ○ | ○ | × | × | × | × |
| SUS 316L | ○ | × | × | × | × | × |
Test conditions:
Immersion in boiling MgCl2 solution, test duration 300h, U-bend test piece is used
○: No stress corrosion cracks
×: Stress corrosion cracking occurred
Weldability
In welding, it is possible to apply ordinary welding methods in the same manner as with stainless steels. Matching composition welding consumables should be used. Post-weld heat treatment is not required.
Heat Treatment
The solution treatment temperature is 1150-1170℃. Rapid cooling is necessary after heat treatment.
Applications
Heat exchangers, centrifugal separators, driers, reaction vessels, salt manufacturing plants, flue gas desulfurization plants.
* Hastelloy is a registered trademark of Haynes International, Inc.
