# Nimonic 901 (UNS N09901) Superalloy: Properties and Applications

Introduction to Nimonic 901

Nimonic 901 (UNS N09901) is a nickel-iron-chromium-based superalloy known for its exceptional strength and corrosion resistance at elevated temperatures. Developed by the British company Wiggin Alloys, this alloy has become a critical material in aerospace and power generation industries where high-temperature performance is paramount.

Chemical Composition

The chemical composition of Nimonic 901 plays a crucial role in its outstanding properties:

• Nickel (Ni): 40-45%
• Chromium (Cr): 11-14%
• Iron (Fe): Balance
• Titanium (Ti): 2.8-3.1%
• Aluminum (Al): 0.9-1.5%
• Carbon (C): ≤0.10%
• Manganese (Mn): ≤1.0%
• Silicon (Si): ≤0.50%
• Copper (Cu): ≤0.50%
• Boron (B): ≤0.01%

Keyword: Nimonic 901 UNS N09901

Mechanical Properties

Nimonic 901 exhibits remarkable mechanical properties that make it suitable for demanding applications:

Property	Value
Tensile Strength	1100-1300 MPa
Yield Strength	700-900 MPa
Elongation	15-25%
Hardness	300-350 HB
Density	8.14 g/cm³

Key Characteristics

Nimonic 901 offers several unique characteristics that contribute to its widespread use:

• High-temperature strength: Maintains excellent mechanical properties up to 650°C (1200°F)
• Oxidation resistance: Forms a protective chromium oxide layer at high temperatures
• Creep resistance: Performs well under prolonged stress at elevated temperatures
• Fatigue resistance: Withstands cyclic loading conditions
• Corrosion resistance: Resists oxidation and other forms of high-temperature corrosion

Heat Treatment

Proper heat treatment is essential to achieve the desired properties in Nimonic 901:

1. Solution treatment: Typically performed at 1080-1120°C (1975-2050°F) followed by rapid cooling
2. Aging: Carried out at 700-800°C (1290-1470°F) for 16-24 hours to precipitate strengthening phases

Applications

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