Alloy N09935 — Precipitation Hardenable Nickel-Iron-Chromium Superalloy
Product Description
FUSHUN METAL is proud to offer premium quality Alloy N09935, an advanced precipitation hardenable nickel-iron-chromium superalloy specifically engineered for applications demanding both high strength and superior corrosion resistance. This versatile material is designed to deliver exceptional performance in aggressive environments where conventional alloys would rapidly deteriorate. With carefully balanced content of chromium, molybdenum, copper, and niobium, Alloy N09935 provides outstanding resistance to pitting, crevice corrosion, and stress corrosion cracking while maintaining excellent mechanical properties across a wide temperature range.
The alloy’s unique composition allows it to be age-hardened to achieve high strength levels while preserving the exceptional corrosion resistance typically associated with solid-solution strengthened alloys. FUSHUN METAL supplies Alloy N09935 in various product forms including round bars, flat bars, plates, and forgings, all manufactured to meet the most stringent industry specifications. This combination of properties makes Alloy N09935 an ideal choice for critical components in oil and gas, chemical processing, marine, and aerospace applications where both mechanical integrity and corrosion resistance are essential requirements.
Standards and Specifications
Alloy N09935 from FUSHUN METAL meets or exceeds the following industry standards and specifications:
| Standard | Designation |
|---|---|
| UNS | N09935 |
| ASTM | B637 (Similar) |
| NACE | MR0175/ISO 15156 |
| API | 6A, 17D |
Chemical Composition
FUSHUN METAL manufactures Alloy N09935 with precise control of chemical composition according to the following typical requirements:
| Element | Content (%) |
|---|---|
| Nickel (Ni) | 43.0 – 47.0 |
| Chromium (Cr) | 19.0 – 21.0 |
| Iron (Fe) | Balance |
| Molybdenum (Mo) | 3.0 – 4.0 |
| Niobium (Nb) + Tantalum (Ta) | 2.5 – 3.5 |
| Copper (Cu) | 1.5 – 2.5 |
| Titanium (Ti) | 1.5 – 2.0 |
| Aluminum (Al) | 0.1 – 0.5 |
| Carbon (C) | 0.03 Max |
| Manganese (Mn) | 0.5 Max |
| Silicon (Si) | 0.5 Max |
| Phosphorus (P) | 0.015 Max |
| Sulfur (S) | 0.010 Max |
| Boron (B) | 0.006 Max |
Role of Key Alloying Elements
- Nickel (43.0-47.0%): Provides the base matrix for the alloy, enhancing corrosion resistance particularly in reducing environments and ensuring structural stability at high temperatures.
- Chromium (19.0-21.0%): Imparts resistance to oxidation and corrosion in oxidizing environments through the formation of a protective oxide layer.
- Molybdenum (3.0-4.0%): Significantly enhances resistance to pitting and crevice corrosion, especially in chloride-containing environments.
- Niobium (2.5-3.5%): Primary strengthening element that forms gamma double prime (Ni₃Nb) precipitates during age hardening, contributing to the alloy’s high strength.
- Copper (1.5-2.5%): Contributes to precipitation hardening and improves resistance to reducing acids.
- Titanium (1.5-2.0%) and Aluminum (0.1-0.5%): Form gamma prime (Ni₃(Al,Ti)) precipitates during aging, enhancing strength and high-temperature stability.
Mechanical Properties
Alloy N09935 from FUSHUN METAL exhibits exceptional mechanical properties in the solution annealed and aged condition:
| Property | Minimum Value | Typical Value |
|---|---|---|
| 0.2% Yield Strength | 120 ksi (827 MPa) | 130 ksi (896 MPa) |
| Tensile Strength | 150 ksi (1034 MPa) | 165 ksi (1138 MPa) |
| Elongation | 20% | 25% |
| Reduction of Area | 30% | 40% |
| Hardness | 32 HRC | 35-40 HRC |
| Charpy V-Notch Impact @ -50°C | 35 Joules | 45 Joules |
Physical Properties
FUSHUN METAL’s Alloy N09935 demonstrates the following typical physical properties:
| Property | Value |
|---|---|
| Density | 8.3 g/cm³ (0.30 lb/in³) |
| Melting Range | 1310-1390°C (2390-2535°F) |
| Thermal Conductivity at 20°C | 11.2 W/m·K (6.5 BTU/hr/ft/°F) |
| Electrical Resistivity | 1.25 μΩ·m at 20°C |
| Coefficient of Thermal Expansion (20-100°C) | 12.5 × 10⁻⁶ /°C (6.9 × 10⁻⁶ /°F) |
| Specific Heat | 435 J/kg·K (0.104 BTU/lb/°F) |
| Young’s Modulus | 210 GPa (30.5 × 10⁶ psi) |
Key Advantages of Alloy N09935
Alloy N09935 from FUSHUN METAL offers several significant advantages that make it a superior choice for demanding applications:
- Exceptional Combination of Properties: Delivers high strength with superior corrosion resistance, offering an optimal balance of mechanical integrity and durability in aggressive environments.
- Outstanding Corrosion Resistance: Exhibits excellent resistance to pitting, crevice corrosion, stress corrosion cracking, and general corrosion in a wide range of media including chloride-containing environments.
- High Strength through Precipitation Hardening: Can be age-hardened to achieve significant strength levels while maintaining good ductility and toughness.
- Excellent Sour Service Performance: NACE MR0175/ISO 15156 compliant for oil and gas applications in H₂S-containing environments.
- Good Fabricability: Can be machined, formed, and welded using conventional techniques with proper procedures.
- Thermal Stability: Maintains its mechanical properties over extended periods at elevated service temperatures.
- Fatigue Resistance: Demonstrates excellent resistance to both high and low cycle fatigue, ensuring long service life in dynamic applications.
- Cryogenic Capability: Retains good toughness and mechanical properties at sub-zero temperatures.
Heat Treatment
FUSHUN METAL supplies Alloy N09935 in both solution annealed and age-hardened conditions. The following heat treatment procedures are recommended to achieve optimal properties:
Solution Annealing
- Temperature: 1040-1080°C (1900-1975°F)
- Holding Time: Sufficient time based on section thickness to ensure complete solutioning (typically 1 hour per inch of thickness)
- Cooling: Rapid cooling (water quenching) to prevent precipitation of undesirable phases
- Purpose: Dissolves precipitates, homogenizes the structure, and prepares the material for age hardening
Age Hardening (Precipitation Hardening)
- Primary Aging: 720-760°C (1330-1400°F) for 8 hours
- Cooling: Furnace cool at 55°C/hour (100°F/hour) to 620-650°C (1150-1200°F)
- Secondary Aging: Hold at 620-650°C (1150-1200°F) for 8 hours
- Final Cooling: Air cool to room temperature
- Result: Formation of strengthening gamma prime (Ni₃(Al,Ti)) and gamma double prime (Ni₃Nb) precipitates
Note: Specific heat treatment parameters may be adjusted based on section thickness and desired mechanical properties. FUSHUN METAL’s technical team can provide customized heat treatment recommendations for your specific application requirements.
Applications
Due to its exceptional combination of high strength and superior corrosion resistance, Alloy N09935 from FUSHUN METAL is ideally suited for numerous demanding applications:
Oil and Gas Industry
- Downhole components for sour service environments
- Wellhead equipment and Christmas trees
- Completion equipment
- Subsurface safety valves
- Packers and flow control components
- High-pressure/high-temperature (HPHT) service components
- Subsea equipment
Chemical Processing
- Pressure vessels for corrosive media
- Heat exchangers in aggressive environments
- Process equipment handling halides
- Pumps and valves for aggressive service
- Reaction vessels
Marine Applications
- Propeller shafts and fasteners
- Offshore platform components
- Seawater handling systems
- Components for marine environments
Aerospace and Defense
- High-strength components requiring corrosion resistance
- Gas turbine components
- Structural elements in marine environments
Power Generation
- Steam generator tubing
- High-temperature fasteners
- Valves and fittings for supercritical applications
Available Product Forms
FUSHUN METAL provides Alloy N09935 in various product forms to meet diverse manufacturing requirements:
Round Bars
| Diameter Range | Length | Surface Condition |
|---|---|---|
| 10mm – 250mm (0.4″ – 10″) | Random or cut-to-length | Black/As-forged, Rough-turned, Precision-ground, Polished |
Flat Bars
| Thickness | Width | Length |
|---|---|---|
| 10mm – 100mm (0.4″ – 4″) | 25mm – 200mm (1″ – 8″) | Random or cut-to-length |
Plates
| Thickness | Width | Length |
|---|---|---|
| 5mm – 50mm (0.2″ – 2″) | Up to 1500mm (60″) | Up to 6000mm (240″) |
Forgings
| Type | Weight Range | Condition |
|---|---|---|
| Open die forgings, rings, discs, blocks | Up to 2000kg | Solution annealed or solution annealed and aged |
Corrosion Resistance
Alloy N09935 from FUSHUN METAL offers outstanding corrosion resistance in a wide range of aggressive environments:
General Corrosion Resistance
The alloy demonstrates excellent resistance to general corrosion in both oxidizing and reducing environments, including:
- Mineral acids (sulfuric, hydrochloric, phosphoric)
- Organic acids
- Alkaline solutions
- Seawater and marine environments
- Industrial atmospheres
Localized Corrosion Resistance
The high chromium and molybdenum content provides superior resistance to:
- Pitting corrosion in chloride-containing environments
- Crevice corrosion under deposits or in tight spaces
- Intergranular corrosion (properly heat treated condition)
Stress Corrosion Cracking Resistance
Alloy N09935 exhibits excellent resistance to stress corrosion cracking in:
- Chloride-containing environments
- Caustic solutions
- Hydrogen sulfide (H₂S) environments (NACE compliant)
Sour Service Performance
The alloy is fully compliant with NACE MR0175/ISO 15156 specifications for oil and gas environments containing hydrogen sulfide (H₂S), demonstrating excellent resistance to:
- Sulfide stress cracking (SSC)
- Hydrogen-induced cracking (HIC)
- Stress-oriented hydrogen-induced cracking (SOHIC)
Fabrication Guidelines
Alloy N09935 can be fabricated using conventional techniques, with the following recommendations:
Machining
- Machining is best performed in the solution annealed condition
- Use rigid tooling setups to minimize chatter and deflection
- Carbide tooling with positive rake angles is recommended
- Lower cutting speeds (compared to stainless steels) are advised
- Adequate cooling and lubrication should be maintained
- Allow for work hardening during machining operations
Welding
- Gas Tungsten Arc Welding (GTAW/TIG) is the preferred method
- Use matching filler metals or ERNiCrMo-3 (Alloy 625 type)
- Maintain clean surfaces free from contamination before welding
- Minimize heat input to prevent hot cracking
- Preheat is generally not required, but may be beneficial for thick sections
- Post-weld heat treatment is recommended to restore corrosion resistance and mechanical properties
Forming
- Perform forming operations in the solution annealed condition
- Higher forces are required compared to austenitic stainless steels
- Minimum bend radius should be at least 2-3 times the material thickness
- Intermediate annealing may be necessary for severe forming operations
- Age hardening heat treatment should be performed after all forming operations are complete
Heat Treatment Considerations
- Ensure proper temperature control during heat treatment
- Use protective atmospheres or vacuum to prevent surface oxidation
- Allow for potential distortion during age hardening
- Fixtures may be required for complex shapes to maintain dimensional stability
Quality Assurance
FUSHUN METAL maintains the highest standards of quality for Alloy N09935:
- Chemical Analysis: Each heat is analyzed using state-of-the-art spectrometers to ensure compositional compliance with specifications
- Mechanical Testing: Comprehensive testing including tensile, hardness, and impact properties
- Microstructural Examination: Verification of proper grain size and precipitate distribution
- Non-Destructive Testing: Ultrasonic, magnetic particle, and liquid penetrant inspection as required
- Corrosion Testing: Material is tested for resistance to specific corrosive environments when required
- Dimensional Inspection: All products undergo thorough dimensional verification
- Certification: Complete material test reports and certification documentation provided with each shipment
- Traceability: Full traceability from melt to final product is maintained
Comparative Advantages
Understanding how Alloy N09935 compares to similar alloys helps in selecting the optimal material for specific applications:
| Characteristic | Alloy N09935 | Alloy N09925 | Alloy N07718 |
|---|---|---|---|
| Yield Strength (Aged) | 120 ksi min | 105 ksi min | 150 ksi min |
| Corrosion Resistance | Excellent | Very Good | Good |
| Pitting Resistance | Superior | Good | Moderate |
| NACE MR0175 Compliance | Yes | Yes | Limited |
| Maximum Service Temperature | ~650°C (1200°F) | ~650°C (1200°F) | ~650°C (1200°F) |
| Cryogenic Properties | Excellent | Good | Excellent |
| Cost Factor | Moderate-High | Moderate | High |
| Optimal Application Area | Corrosive environments requiring high strength | General purpose with good corrosion resistance | High-strength applications with moderate corrosion concerns |
Why Choose FUSHUN METAL for Alloy N09935
Selecting FUSHUN METAL as your supplier for Alloy N09935 provides numerous advantages:
- Material Expertise: Our team of metallurgists and engineers has extensive experience with nickel-based superalloys and their applications
- Manufacturing Excellence: State-of-the-art production facilities with strict quality control ensure consistent properties
- Comprehensive Testing: All products undergo thorough testing to verify mechanical properties and corrosion resistance
- Custom Solutions: Ability to tailor product specifications to meet specific application requirements
- Technical Support: Expert assistance with material selection, heat treatment, and fabrication guidelines
- Global Supply Capability: Worldwide distribution network ensures timely delivery
- Industry Compliance: All products meet or exceed relevant industry standards
- Competitive Pricing: Excellent value proposition for premium superalloy products
Request Information
Contact FUSHUN METAL today to discuss your Alloy N09935 requirements. Our technical team is ready to assist you with:
- Detailed technical specifications
- Custom size and property requirements
- Fabrication recommendations
- Application-specific material selection guidance
- Price quotations and delivery schedules
- Material certification and testing requirements
