Comprehensive Overview of ASTM B163 N02200 Seamless Tubes: Properties, Production, and Applications

December 25, 2025

Introduction

ASTM B163 is a widely recognized standard for seamless nickel and nickel-alloy condenser and heat-exchanger tubes, designed for high-temperature and corrosive environments. Among the alloys specified in this standard, N02200 (Commercially Pure Nickel Grade 200) stands out as a versatile material due to its exceptional corrosion resistance, thermal stability, and mechanical integrity. This article provides a detailed overview of ASTM B163 N02200 seamless tubes, covering their composition, properties, production processes, and key applications.

Material Composition and Classification

ASTM B163 N02200 is classified as commercially pure nickel with a minimum nickel content of 99.0% (by weight), making it one of the most refined nickel grades available. The alloy’s chemical composition is tightly controlled to minimize impurities, ensuring consistent performance. Key elements include:

Nickel (Ni): ≥99.0% (typically 99.2–99.8%)
Carbon (C): ≤0.15% (to reduce carbide precipitation)
Manganese (Mn): ≤0.35% (enhances workability)
Iron (Fe): ≤0.40% (trace impurity)
Silicon (Si): ≤0.35% (trace impurity)
Sulfur (S) and Phosphorus (P): ≤0.015% each (minimizes brittleness).

This high-purity composition distinguishes N02200 from other nickel alloys (e.g., Ni-Cu or Ni-Cr alloys) and underpins its unique properties.

Key Properties of ASTM B163 N02200 Seamless Tubes

1. Corrosion Resistance

The primary advantage of N02200 lies in its outstanding resistance to a wide range of corrosive media, including:

Neutral and alkaline solutions: Resistant to sodium hydroxide (NaOH), potassium hydroxide (KOH), and ammonium hydroxide (NH₄OH) at temperatures up to 100°C (212°F).
Non-oxidizing acids: Exhibits excellent resistance to dilute sulfuric acid (H₂SO₄) and hydrochloric acid (HCl) at low concentrations (≤10%).
Chloride-containing environments: Withstands pitting and crevice corrosion in seawater and brine, though less resistant than higher-nickel alloys like Alloy 625.
High-temperature oxidation: Retains stability in air up to 600°C (1112°F), forming a passive oxide layer that inhibits further degradation.

Its corrosion resistance makes it ideal for use in chemical processing, where exposure to aggressive fluids is common.

2. Mechanical Properties

N02200 maintains robust mechanical strength across a broad temperature range, critical for structural integrity in demanding applications:

Tensile Strength: ~380–550 MPa (55–80 ksi) at room temperature; retains ~50% strength at 600°C (1112°F).
Yield Strength: ~105–240 MPa (15–35 ksi) at room temperature.
Elongation: ≥30% (indicating good ductility for forming and bending).
Hardness: Brinell hardness (HBW) of 95–120, which can be increased via cold working but is typically annealed to restore ductility.

Cold working (e.g., rolling, drawing) enhances strength but may induce work hardening, requiring subsequent annealing (at 700–870°C/1292–1598°F) to relieve stress.

3. Thermal and Electrical Conductivity

As a nearly pure metal, N02200 exhibits excellent thermal conductivity (~90 W/m·K at 20°C), making it suitable for heat transfer applications. Its electrical conductivity (~14.3 MS/m at 20°C) is also high, though less commonly exploited in tube applications.

4. Fabrication Characteristics

N02200 is highly formable and weldable:

Forming: Can be bent, flared, or deep-drawn without cracking, even at room temperature.
Welding: Compatible with gas tungsten arc welding (GTAW/TIG), gas metal arc welding (GMAW/MIG), and resistance welding. Filler metals such as ENi-1 (AWS A5.14) are recommended to maintain corrosion resistance.

Production Process of ASTM B163 N02200 Seamless Tubes

Seamless tubes are manufactured through a multi-step process to ensure dimensional precision, uniformity, and mechanical integrity:

Melting and Casting: High-purity nickel (≥99.0%) is melted in electric arc furnaces (EAFs) or vacuum induction furnaces (VIFs) to minimize impurities. The molten metal is cast into billets or ingots.
Hot Extrusion/Piercing: Billets are heated to 1100–1250°C (2012–2282°F) and pierced using a mandrel to form a hollow shell, followed by extrusion through a die to achieve the desired outer diameter.
Cold Drawing/Rolling: The hollow shell is drawn through a series of dies or rolled using mandrels to reduce wall thickness and improve surface finish. Multiple passes may be required to reach final dimensions.
Annealing: After cold working, tubes are annealed at 700–870°C (1292–1598°F) in a controlled atmosphere (e.g., hydrogen or argon) to relieve internal stresses and restore ductility.
Finishing: Tubes undergo straightening, cutting to length, and surface treatment (e.g., pickling, passivation) to remove oxides and enhance corrosion resistance. Final inspection includes non-destructive testing (NDT) such as ultrasonic or eddy current testing to detect defects.

Applications of ASTM B163 N02200 Seamless Tubes

Due to its unique combination of corrosion resistance, thermal stability, and mechanical strength, ASTM B163 N02200 seamless tubes are widely used in industries requiring reliable performance in harsh environments:

Chemical Processing: Used in heat exchangers, condensers, and reactors handling caustic soda, organic acids, and neutral salt solutions. Their resistance to chloride-induced stress corrosion cracking (SCC) makes them suitable for brine systems.
Power Generation: Employed in steam generators, condensers, and cooling systems where high-temperature water/steam resistance is critical. They are also used in nuclear power plants for auxiliary heat exchangers.
Aerospace and Marine Engineering: Applied in exhaust systems, fuel lines, and seawater-cooled components due to their lightweight nature (density ~8.9 g/cm³) and corrosion resistance to marine environments.
Electronics and Semiconductors: Used in plating tanks, electrode assemblies, and high-purity fluid handling systems, leveraging their inertness to avoid contamination.
Food and Pharmaceutical Industries: Utilized in processing equipment (e.g., evaporators, sterilizers) where resistance to cleaning agents and compliance with hygiene standards (e.g., FDA) is essential.

Conclusion

ASTM B163 N02200 seamless tubes represent a cornerstone of materials engineering for applications demanding superior corrosion resistance, thermal stability, and mechanical reliability. Their high-purity nickel composition, combined with precise manufacturing processes, ensures consistent performance in extreme environments—from chemical reactors to aerospace systems. As industries continue to prioritize durability and efficiency, the role of N02200 tubes in critical infrastructure remains indispensable.

For engineers and procurement specialists, understanding the properties and capabilities of ASTM B163 N02200 seamless tubes is key to selecting the right material for long-term operational success.

Contact Person :	Mr. admin
Tel :	15116256436
Fax :	86-731-8426-1658