Incoloy 27-7MO (Alloy 27-7MO, UNS S31277) Wire Description:
Inconel®, Incoloy® and Monel® are registered trademarks of Special Metals Corporation and its subsidiaries.
Incoloy 27-7MO is a superaustenitic steel containing 7% molybdenum. It exhibits greater corrosion resistance in most environments than superaustenitic steels with 6% molybdenum. In many environments, Incoloy 27-7MO (UNS S31277) achieves corrosion resistance levels that approximate those of higher alloyed materials such as INCONEL alloys 625, 22 and C-276.
Incoloy 27-7MO products typically contain 27% nickel, 22% chromium, 7.2% molybdenum and 0.34% nitrogen. The molybdenum, chromium and nitrogen content affords resistance to pitting and crevice corrosion. Nickel, nitrogen and molybdenum provide resistance towards reducing media, while a high chromium content offers resistance towards oxidising media. Incoloy 27-7MO is suitable for use in mixed acid environments, particularly those that contain both oxidising and reducing acids.
Other Trade Names: Alloy 27-7MO, UNS S31277

Specifications for Wire produced from Incoloy Alloy 27-7MO:
Metal Type: UNS S31277
Standard: ASTM A 479/ASME SA 479
Chemical Composition, %.
|
Ni |
Cr |
Mo |
Mn |
Cu |
Si |
N |
P |
C |
S |
Fe |
Minimum |
26 |
20.5 |
6.5 |
|
0.5 |
|
0.3 |
|
|
|
Balance |
Maximum |
28 |
23 |
8 |
3.0 |
1.5 |
0.5 |
0.4 |
0.03 |
0.02 |
0.01 |
Applications of Incoloy 27-7MO:
Incoloy 27-7MO is employed in various industrial sectors. Its chemical composition and performance data substantiate its use under demanding conditions.
- Chemical Processing:
- The alloy is applied in the chemical industry given its measured corrosion resistance in aggressive chemical environments.
- Shipbuilding:
- The alloy is utilised in shipbuilding because resistance to sea water and salt-spray corrosion is required.
- Pollution Control Facilities:
- The alloy is incorporated in environmental control installations given its resistance to corrosive gases and chemicals.
- Pulp and Paper Industry:
- The alloy is used in components for pulp and paper processing to fulfil corrosion resistance criteria.
- Oil and Gas Production:
- The alloy is applied in oil and gas production since corrosion resistance is essential for the longevity of equipment.