Incoloy® 925 is a high-performance nickel-iron-chromium alloy renowned for its exceptional strength and corrosion resistance, especially in demanding environments. Engineered to withstand harsh chemical exposure, high pressures, and extreme temperatures, it is frequently used in industries such as oil and gas, marine, aerospace, and chemical processing. Its superior resistance to sulfide stress cracking and pitting makes it ideal for downhole and surface gas well components, valves, and high-strength fasteners. Whether operating in deep-sea exploration or corrosive industrial settings, Incoloy® 925 delivers long-term reliability and performance where lesser materials fail.
At Nickel Systems, we specialize in supplying premium Incoloy® 925 products that meet the rigorous specifications of your project. Our experienced team is ready to provide material expertise, inventory availability, and competitive pricing.
Contact us today to begin your custom quote and experience the Nickel Systems advantage.
Environment: Severe Environments: Hot Concentrated Acids & Chemicals
Temperature Limit: 1200 °F
/ 649 °C
Ultimate Tensile (Typical): 130 ksi / 896 mpa
Incoloy® 925 Specifications
Check out all our technical data below for Incoloy® 925 material. If your questions are not answered, download the Incoloy® 925 Technical Data Sheet Here.
Incoloy® 925 Specifications
Institution
Standard
Description
ASTM
B805
Rod, bar, wire, forging stock, and forgings
B564
Forgings, forged fittings, flanges
B704
Welded pipe and tubing
B705
Seamless pipe & tubing
ASME
SB-805, SB-564, SB-704, SB-705
Boiler and pressure vessel-grade rod, bar, tube, pipe, & forgings
DIN / EN
10088-1, 10088-2
Plate, sheet, strip, bars, & rods
JIS
H4554
Seamless & welded tubes
H4552
Rod & bars
ISO
6208
Tubing
15156 / Nace MR0175
Bar, tubing, & fittings
Incoloy® 925 Chemical Composition
Element
% Composition
Description
Nickel (Ni)
42-46%
Range
Chromium (Cr)
19.5-22.5%
Range
Iron (Fe)
22%
Minimum
Molybdenum (Mo)
1.5-3%
Range
Copper (Cu)
1.5-3.0%
Range
Titanium (Ti)
1.9-2.4%
Range
Aluminum (Al)
0.1-0.5%
Range
Manganese (Mn)
1%
Maximum
Silicon (Si)
0.5%
Maximum
Niobium (Nb)
0.5%
Maximum
Carbon (C)
0.03%
Maximum
Sulfur (S)
0.03%
Maximum
Incoloy 925 Physical Properties
Property
Value
Units
Density
0.292
lb/in³
8.08
g/cm³
Melting Range
2,392-2,490
℉
1,311-1,366
℃
Electrical Resistivity
701
ohm●cmil/ft
1.17
µΩ●m
Permeability at 200 oersteds (15.9 kA/m)
1.001
Incoloy 925 Mechanical Properties
Material
Tensile Strength
0.2% Offset Yield Strength
% Elongation
Hardness Rockwell
Round/Solution-Annealed
99 ksi
39.3 ksi
56 %
76 B
685 MPa
271 MPa
,
Round/Solution-Annealed & Aged
167.3 ksi
120.6 ksi
27 %
32 C
1,154 MPa
832 MPa
Cold Drawn Tubing/Solution-Annealed & Aged
172.5 ksi
120.4 ksi
27 %
35 C
1,189 MPa
830 MPa
This table describes mechanical property limits for Incoloy 925, Solution-Annealed and Aged Material.
Incoloy® 925 Mechanical Property Limits
Property
Cold Worked
Hot Worked
Diameter
5/8 to 3.0 in
1 to 10 in
15.9 to 76.2 mm
25.4 to 254 mm
Tensile Strength Minimum
140 ksi
105 ksi
965 MPa
758 MPa
0.2% Offset Yield Strength
18 %
18 %
Reduction of Area Minimum
25 %
25 %
Impact Strength Min Average
35 ft ● lbf
4.85 kgf ● m
35 ft ● lbf
4.85 kgf ● m
Hardness Rockwell C
26 min to 38 max
26 min to 38 max
Charpy V-Notch – Impact tests performed at -75℉ (-60℃) in accordance with ASTM E23. Capability of meeting the strengths shown at room temperature is guaranteed. Hardness testing in accordance with ATM E18.
Incoloy 925 Thermal Properties
Temperature
Coefficient of Expansion
Specific Heat
℉
10^(-6) in/in●℉
Btu/lb●℉
70
-
0.104
200
7.8
0.109
400
8.1
0.116
600
8.4
0.122
800
8.5
0.129
1,000
8.7
0.136
1,200
9.0
0.143
1,400
9.5
0.150
1,600
-
0.157
Temperature
Coefficient of Expansion
Specific Heat
℃
µm/m●℃
J/kg●℃
100
-
435
200
13.2
456
300
14.7
486
400
15.0
532
500
15.3
561
600
15.7
586
700
16.3
611
800
17.2
641
900
-
666
Incoloy® 925 Physical Properties at High Temperatures
Temperature
Young's Modulus
Shear Modulus
Poisson's Ratio
℉
℃
10³ ksi
GPa
10³ ksi
GPa
70
21
28.9
199
11.2
77
0.293
100
38
28.8
199
11.1
76
0.299
200
93
28.3
195
10.8
75
0.308
300
149
27.8
192
10.6
73
0.316
400
204
27.3
188
10.4
72
0.315
500
260
26.8
185
10.2
70
0.317
600
316
26.3
182
10.0
69
0.319
700
371
25.9
178
9.8
68
0.319
800
427
25.4
175
9.6
66
0.323
900
482
24.9
172
9.4
65
0.323
1,000
538
24.4
168
9.2
64
0.324
1,100
593
23.8
164
9.0
62
0.326
1,200
649
23.2
160
8.7
60
0.330
1,300
704
22.5
155
8.4
58
0.334
1,400
760
21.8
150
8.2
56
0.338
1,500
816
21.0
145
7.9
54
0.335
1,600
871
20.1
139
7.6
52
0.330
1,700
927
19.2
132
7.2
50
0.326
A table showing the mechanical properties at high temperatures of solution-annealed and aged for Incoloy® 925.
Incoloy 925 Elevated Temperature Thermophysical Properties
Incoloy® 925 is a nickel-iron-chromium alloy designed for high strength and corrosion resistance, especially in harsh environments such as those encountered in the oil and gas industry. It is designated under the UNS number N09925 and is part of the Incoloy® family developed by Special Metals Corporation.
High strength due to precipitation hardening (age-hardening)
Resistance to stress corrosion cracking, pitting, & crevice corrosion
Good mechanical properties at both room and elevated temperatures.
Other Names of Incoloy® 925
UNS N09925
Nickel-Iron-Chromium Alloy
BS EN 10204
Nickel Alloy UNS N09925
En 10088-2
Werkshoff 2.4858
DIN NiCr21MoFeCuTi
NiFeCrMoCuTi Alloy
Chemical Composition of Incoloy® 925
Check out our pie chart breaking down the chemical composition of Incoloy 925. Find out more information below it about how its different elements add to its corrosion resistance and high performance in extreme environments.
Incoloy® 925’s Corrosion Resistance Performance
There are many types of corrosion that need to be considered when selecting a high performance material. Here is a brief description of Incoloy® 925’s resistance to these types of corrosion.
General Corrosion
Performance: Excellent
Incoloy® 925 shows outstanding resistance to general (uniform) corrosion in a wide range of oxidizing and reducing environments.
Its high nickel and chromium content ensures stability in sour gas, acidic solutions, and chloride-rich environments.
Commonly used in acid service (e.g., sulfuric, phosphoric, and nitric acids).
Incoloy® 925 Corrosion Comparison in Free-Sulfur Environments
Incoloy® 925 Corrosion Comparison in Free-Sulfur Environments
Notes: (1) Autoclave tests a 15-day duration on unstressed coupons. (2) Solution A: 15% NaCl plus 200psi H₂S plus 100 psi CO₂ plus 1 g/l of sulfur at 450℉. (3) Solution B: 25% NaCl plus 200 psi H₂S plus 100 psa.
Pitting is caused by localized attack, typically in chloride-containing media.
Molybdenum in the alloy helps suppress pitting initiation.
Suitable for use in seawater, brine, and produced fluids in oil wells.
Crevice Corrosion
Performance: Good to Very Good
Incoloy® 925 handles tight crevices or stagnant fluid conditions better than many stainless steels due to its protective passive film, bolstered by chromium and molybdenum.
Performance is optimized in well-designed components that reduce fluid stagnation.
Stress Corrosion Cracking (SCC)
Performance: Excellent in chloride and H₂S environments
SCC is a major threat in oilfield and marine applications, especially under tensile stress and chloride exposure.
The high nickel content significantly improves resistance to chloride-induced SCC.
Also highly resistant to sulfide stress corrosion cracking (SSCC), making it compliant with NACE MR0175 / ISO 15156 for sour gas service.
Intergranular Corrosion
Performance: Excellent
Due to the titanium content, Incoloy® 925 resists sensitization (chromium carbide precipitation at grain boundaries), which prevents intergranular attack even after welding or heat exposure.
Erosion-Corrosion
Performance: Good
Offers moderate resistance to erosion-corrosion, where mechanical wear combines with corrosive fluid attack (common in high-velocity flow or sand-laden fluids).
Tougher than many stainless steels, but flow design considerations are still important for long-term service.
Galvanic Corrosion
Performance: Good with similar alloys
Can be safely paired with other high-nickel alloys in multi-metal systems.
May corrode when in electrical contact with more noble materials (e.g., titanium or noble metals) in conductive environments—careful material pairing is advised.
Why Oil & Gas Depends on Incoloy® 925?
The oil and gas industry is the primary and most significant user of Incoloy 925 (UNS N09925). This alloy was specifically engineered to meet the mechanical and environmental challenges encountered in sour (H₂S-containing) oilfields, offshore drilling platforms, and high-pressure downhole environments.
Sour Service Resistance: Certified for use under NACE MR0175 / ISO 15156, Incoloy® 925 is resistant to sulfide stress cracking (SSC), a critical requirement for sour gas wells.
High Mechanical Strength:Precipitation hardening enables it to maintain high yield and tensile strength, crucial for load-bearing components under extreme pressure and temperature.
Corrosion Resistance in Harsh Fluids: With resistance to chloride-induced stress corrosion cracking, pitting, and crevice corrosion, it performs well in: Brine, Seawate, & Produced fluids containing CO₂ and H₂S.
Description: Engineered bolts, pins, or threaded connectors manufactured per drawing or spec.
Use: Specialty applications like completion tools, mandrels, or hydraulic assemblies.
Advantage: Tailored to exact dimensional, strength, and corrosion criteria.
While Incoloy® 925 may not offer the same level of corrosion resistance as Inconel® 625—especially in severely oxidizing or chloride-rich environments—it excels where strength, sour service resistance, and cost-efficiency are equally critical. Its precipitation-hardenable structure provides significantly higher mechanical strength, making it ideal for demanding oil and gas applications such as downhole equipment, tubing hangers, and pressure-retaining components. It remains fully NACE MR0175/ISO 15156 compliant for sour gas service, and its lower nickel and molybdenum content makes it more economical without compromising reliability. This unique balance of performance and value positions Incoloy® 925 as the optimal choice for high-stress, corrosive environments where both strength and budget matter. Contact Nickel Systems today to speak with a materials expert and receive a custom quote tailored to your project’s requirements.
Nickel Systems provides high-quality exotic-grade materials that hold up in the toughest, most severe heat and corrosive environments. With our large inventory of specialty fasteners in stock, we are always ready to serve the most challenging applications.
