Incoloy 945 / 945X Alloy
High-Strength, Corrosion-Resistant Nickel-Iron-Chromium Alloy for Oil & Gas Applications
Supplied by Huaxiao-Alloy – Your Trusted Global Alloy Partner
Incoloy® 945 and Incoloy® 945X are precipitation-hardenable nickel-iron-chromium alloys developed specifically for severe oil & gas, chemical processing, and sour service environments. These alloys provide an exceptional balance of high mechanical strength, excellent resistance to corrosion, stress corrosion cracking (SCC), hydrogen embrittlement, and sulfide stress cracking (SSC).
Huaxiao-Alloy supplies Incoloy 945 / 945X Alloy in all product forms, with full compliance to ASTM, ASME, UNS, NACE, and ISO standards, serving upstream, midstream, and downstream projects worldwide.
1. Incoloy 945 / 945X Alloy Overview
Incoloy 945 and its enhanced variant Incoloy 945X were engineered to address the increasing demands of deep-well drilling, high-pressure/high-temperature (HPHT) wells, and aggressive chloride- and sulfide-containing environments.
Key Design Objectives:
High yield and tensile strength after aging
Excellent resistance to pitting, crevice corrosion, and SCC
Superior performance in sour gas (H₂S) environments
Improved fatigue and fracture toughness
Compliance with NACE MR0175 / ISO 15156
Incoloy 945X offers optimized chemistry and processing for enhanced corrosion resistance and toughness, particularly in extreme HPHT conditions.
2. Chemical Composition (%)
Incoloy 945 / 945X (Typical Range)
| Element | Content (%) |
|---|---|
| Nickel (Ni) | 42.0 – 46.0 |
| Chromium (Cr) | 18.0 – 21.0 |
| Iron (Fe) | Balance |
| Molybdenum (Mo) | 2.5 – 4.0 |
| Copper (Cu) | 2.5 – 4.0 |
| Niobium (Nb) | 2.5 – 3.5 |
| Titanium (Ti) | 0.5 – 1.0 |
| Aluminum (Al) | 0.3 – 0.7 |
| Carbon (C) | ≤ 0.03 |
| Manganese (Mn) | ≤ 0.50 |
| Silicon (Si) | ≤ 0.50 |
| Sulfur (S) | ≤ 0.010 |
📌 Metallurgical Advantage:
The combined Nb-Ti-Al precipitation system provides high strength, while Cr-Mo-Cu additions deliver excellent resistance to chloride- and sulfide-induced corrosion.
3. Mechanical Properties
Solution Annealed + Aged (Typical)
| Property | Incoloy 945 | Incoloy 945X |
|---|---|---|
| Tensile Strength | ≥ 1100 MPa | ≥ 1150 MPa |
| Yield Strength (0.2%) | ≥ 760 MPa | ≥ 820 MPa |
| Elongation | ≥ 20% | ≥ 18% |
| Hardness | 32 – 38 HRC | 34 – 40 HRC |
| Impact Toughness | Excellent | Superior |
Actual properties depend on product form and heat-treatment condition.
4. Physical Properties
| Property | Value |
|---|---|
| Density | ~8.10 g/cm³ |
| Melting Range | 1340 – 1400°C |
| Thermal Conductivity | 11.5 W/m·K |
| Electrical Resistivity | ~1.20 μΩ·m |
| Elastic Modulus | ~200 GPa |
5. Key Features & Advantages
🛡️ Outstanding Corrosion Resistance
Excellent resistance to pitting, crevice corrosion, SCC, and SSC in chloride- and H₂S-containing environments.
💪 High Strength After Aging
Maintains high mechanical performance in HPHT oil & gas service.
🔥 Sour Service Approved
Qualified for NACE MR0175 / ISO 15156 applications.
🔩 Excellent Fatigue & Fracture Toughness
Ideal for dynamic and cyclic loading conditions.
6. Available Product Forms (Huaxiao-Alloy Supply)
Huaxiao-Alloy supplies Incoloy 945 / 945X Alloy in full commercial and custom forms:
Tubular Products
Seamless pipes
Thick-wall tubes
OCTG components
Downhole tubing
Flat Products
Plates
Sheets
Strips
Long Products
Round bars
Forged bars
Shafts
Wire & wire rod
Precision & Custom Components
Packers & mandrels
Valve bodies
Fasteners
Subsea components
CNC-machined parts
7. Standards & Equivalent Grades
| Standard | Designation |
|---|---|
| UNS | N09945 |
| ASTM | B637 |
| ASME | SB-637 |
| NACE | MR0175 / ISO 15156 |
| ISO | Oil & gas sour service compliant |
| EN / DIN | Available upon request |
📄 Documentation: EN 10204 3.1 / 3.2, PMI, H₂S SSC test reports available
8. Corrosion & Sour Service Performance
Incoloy 945 / 945X demonstrate excellent resistance in:
High-chloride brines
Sour gas environments (H₂S + CO₂)
Acidic production fluids
High-pressure seawater systems
HPHT wells
945X offers enhanced resistance to localized corrosion and cracking compared with standard 945.
9. Typical Applications
Oil & Gas (Primary Use)
Downhole tools
Packers & mandrels
Safety valves
Subsea equipment
Completion hardware
Chemical Processing
Pressure vessels
Heat exchangers
High-strength fasteners
Energy & Offshore
Offshore platforms
Seawater handling systems
HPHT structural components
10. Heat Treatment & Fabrication Guide
Heat Treatment
Solution annealing: ~980°C, air cool
Aging: 700–750°C for precipitation hardening
Machining
Machinable in annealed condition
Carbide tools recommended
Welding
GTAW / GMAW / SMAW
Weld in solution-annealed condition
Post-weld aging required for strength restoration
11. Quality Control & Inspection
Huaxiao-Alloy guarantees:
Chemical composition verification
Mechanical & hardness testing
SSC / SCC testing (on request)
Ultrasonic & surface inspection
PMI testing
Dimensional inspection
Full traceability & mill test certificates
12. Why Choose Huaxiao-Alloy for Incoloy 945 / 945X?
✔ Certified oil & gas mill sources
✔ NACE-compliant materials
✔ HPHT project experience
✔ Custom heat treatment & machining
✔ Export-ready packaging
✔ Competitive pricing & reliable lead times
📍 Facilities: Wuxi · Foshan · Shanghai Baoshan
🌍 Global Supply: North America · Europe · Middle East · Southeast Asia
945X offers enhanced corrosion resistance and toughness for extreme HPHT conditions.
Yes, it complies with NACE MR0175 / ISO 15156.
In many corrosion-critical applications, yes—especially where SCC resistance is required.
Yes, SSC and SCC test reports are available on request.
Bars, forgings, thick-wall tubes, and machined components.
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