# Nickel Alloy UNS N02200: Properties and Applications

## Introduction to UNS N02200

Nickel Alloy UNS N02200, also known as commercially pure nickel, is a versatile material with excellent corrosion resistance and high thermal and electrical conductivity. This alloy is widely used in various industries due to its unique combination of properties.

## Chemical Composition

The chemical composition of UNS N02200 is primarily nickel (Ni) with small amounts of other elements:

– Nickel (Ni): 99.0% min
– Carbon (C): 0.15% max
– Manganese (Mn): 0.35% max
– Iron (Fe): 0.40% max
– Silicon (Si): 0.35% max
– Copper (Cu): 0.25% max
– Sulfur (S): 0.01% max

## Physical Properties

UNS N02200 exhibits several notable physical properties:

– Density: 8.89 g/cm³ (0.321 lb/in³)
– Melting Point: 1435-1446°C (2615-2635°F)
– Electrical Resistivity: 6.84 μΩ·cm at 20°C
– Thermal Conductivity: 70 W/m·K at 20°C
– Coefficient of Thermal Expansion: 13.3 μm/m·K (20-100°C)

## Mechanical Properties

The mechanical properties of UNS N02200 vary depending on the temper and form:

### Annealed Condition

– Tensile Strength: 317-379 MPa (46-55 ksi)
– Yield Strength (0.2% offset): 59-103 MPa (8.5-15 ksi)
– Elongation: 40-50%
– Hardness: 45-65 HRB

### Cold Worked Condition

– Tensile Strength: up to 758 MPa (110 ksi)
– Yield Strength (0.2% offset): up to 690 MPa (100 ksi)
– Elongation: 2-15%
– Hardness: up to 90 HRB

## Corrosion Resistance

UNS N02200 offers excellent corrosion resistance in various environments:

– Resistant to caustic alkalis up to melting point
– Good resistance to neutral and alkaline salt solutions
– Excellent performance in reducing environments
– Resistant to dry halogen gases at room temperature
– Performs well in food processing applications

## Applications of UNS N02200

Due to its unique properties, UNS N02200 finds applications in numerous industries:

### Chemical Processing

– Caustic handling equipment
– Chlorine production components
– Hydrogen fluoride processing

### Electronics

– Lead frames
– Battery components
– Electronic housings

### Food Processing

– Food handling equipment
– Processing vessels
– Transfer piping

### Other Applications

– Marine engineering components
– Aerospace applications
– Nuclear engineering
– Coinage

## Fabrication and Welding

UNS N02200 can be readily fabricated using standard techniques:

### Forming

– Excellent cold working properties
– Can be hot worked between 650-1230°C (1200-2250°F)
– Annealing recommended after severe cold work

### Machining

– Similar to austenitic stainless steels
– Use positive rake angles and sharp tools
– Recommended cutting fluids for heavy cuts

### Welding

– Can be welded using common techniques (TIG, MIG, SMAW)
– No preheating required
– Post-weld annealing may be necessary for critical applications

## Conclusion

Nickel Alloy UNS N02200 is a highly versatile material with excellent corrosion resistance, good mechanical properties, and outstanding thermal and electrical conductivity. Its wide range of applications across multiple industries makes it an essential material for engineers and designers working with demanding environments. The