# Alloy N UNS N10003: Properties and Applications

## Introduction to Alloy N UNS N10003

Alloy N UNS N10003 is a nickel-based alloy known for its exceptional resistance to corrosion and high-temperature stability. This material is widely used in industries where extreme conditions demand reliable performance from structural components.

## Chemical Composition

The chemical composition of Alloy N UNS N10003 includes:

– Nickel (Ni): Primary element (approximately 67%)
– Chromium (Cr): 6-8%
– Iron (Fe): 4-6%
– Molybdenum (Mo): 15-17%
– Tungsten (W): 3-4.5%
– Cobalt (Co): ≤2.5%
– Other elements in smaller quantities

## Physical Properties

Alloy N UNS N10003 exhibits several notable physical properties:

– Density: 8.89 g/cm³
– Melting Point: 1320-1370°C (2410-2500°F)
– Thermal Conductivity: 9.8 W/m·K at 100°C
– Electrical Resistivity: 128 μΩ·cm at 20°C
– Modulus of Elasticity: 217 GPa (31.5 × 10⁶ psi)

## Mechanical Properties

The mechanical properties of Alloy N make it suitable for demanding applications:

– Tensile Strength: 690-895 MPa (100-130 ksi)
– Yield Strength: 310-690 MPa (45-100 ksi)
– Elongation: 30-50%
– Hardness: 150-250 HB

## Corrosion Resistance

Alloy N UNS N10003 offers outstanding corrosion resistance in various environments:

– Excellent resistance to reducing acids like hydrochloric, sulfuric, and phosphoric acids
– Good resistance to oxidizing environments
– Superior performance in chloride-containing solutions
– Resistance to pitting and crevice corrosion in seawater applications

## High-Temperature Performance

This alloy maintains its properties at elevated temperatures:

– Good oxidation resistance up to 1095°C (2000°F)
– Retains strength and creep resistance at high temperatures
– Minimal carbide precipitation during prolonged exposure to high temperatures

## Fabrication and Welding

Alloy N UNS N10003 can be fabricated using standard techniques:

– Hot working should be performed between 980-1205°C (1800-2200°F)
– Cold working requires intermediate annealing
– Welding can be performed using GTAW, GMAW, and SMAW methods
– Post-weld heat treatment is generally not required

## Applications of Alloy N UNS N10003

This versatile alloy finds applications in numerous industries:

### Chemical Processing

– Reactors and vessels for aggressive chemical environments
– Heat exchangers and piping systems
– Components for sulfuric and hydrochloric acid production

### Oil and Gas Industry

– Downhole components
– Flare stacks
– Offshore platform equipment

### Power Generation

– Gas turbine components
– Heat recovery systems
– Nuclear reactor components

### Other Applications

– Pollution control equipment
– Pharmaceutical processing equipment
– Marine applications

## Comparison with Other Nickel Alloys

Alloy N UNS N10003 offers several advantages over similar materials:

– Better corrosion resistance than Alloy 625 in certain environments
– Higher molybdenum content than Alloy C-276 for improved resistance to reducing acids
– More cost-effective than some other nickel alloys while maintaining performance

## Conclusion

Alloy N UNS N10003 is a high-performance nickel alloy that combines excellent corrosion resistance with good mechanical properties at elevated temperatures. Its versatility makes it suitable for a wide range of demanding applications across multiple industries. When selecting materials for harsh environments, Alloy N should be considered for its proven reliability and long-term performance.