Material Family

Nickel-Chromium-Iron Superalloy (Solid-Solution Strengthened)

Distinguished from stainless steel by its high nickel content for superior corrosion and heat resistance.

Common Forms (Bar)

Hot Finished or Cold Finished Rounds, Hexagons, Squares, Rectangles. Also available as Forged Bar for larger cross-sections.

Supplied in straight lengths or coils (small diameter wire rod).

Chemical Composition (Typical wt.%)

Ni: ≥ 72.0 (Balance)
Cr: 14.0 - 17.0
Fe: 6.0 - 10.0
C: ≤ 0.15
Mn: ≤ 1.00
Si: ≤ 0.50

High Nickel (Ni) provides inherent corrosion resistance. Chromium (Cr) confers oxidation resistance.

Mechanical Properties (Annealed, Room Temp)

Tensile Strength (Rm): 550 - 690 MPa
Yield Strength (Rp0.2): 240 - 345 MPa
Elongation (A): ≥ 30%
Hardness: Typically 70-85 HRB

Robust strength maintained over a wide temperature range. Can be cold worked to higher strengths.

Physical Properties

Density: 8.47 g/cm³
Melting Range: 1370 - 1425 °C
Max Continuous Service Temp: 1175°C (2150°F) in oxidizing atmospheres.

Higher density than steel. Exceptional thermal stability.

Key Corrosion Resistance

• Excellent resistance to oxidation at high temperatures.

• Excellent resistance to chloride-ion stress-corrosion cracking.

• Good resistance to corrosion by high-purity water, organic acids, and alkalis.

Ideal for components in heat treating, chemical processing, and nuclear applications.

Key Standards (Bar)

ASTM B166 / ASME SB-166 (Standard Specification for Nickel-Chromium-Iron Alloy Rod, Bar, and Wire), AMS 5665 (Aerospace)

ASTM B166 is the primary material specification for bar products.

Common Sizes & Conditions

Diameter/Thickness: 3mm (1/8") up to 300mm (12")+ diameter.
Condition: Annealed (Soft), Hot Finished, or Cold Finished. Can be supplied in strain-hardened tempers (e.g., 1/4 Hard, 1/2 Hard).

Condition selection balances machinability/fabricability with final part strength requirements.

Machinability & Fabrication

Machinability Rating: ~25% (compared to 100% for B1112 steel). Tough and gummy; requires positive rake angles, sharp tools, and heavy feeds.
Weldability: Excellent, using matching filler metal (ERNiCr-3).

More difficult to machine than steel; proper techniques are essential for good tool life and finish.

Typical Bar Applications

• Fasteners: High-temperature bolts, studs, nuts.
• Valve & Pump Components: Stems, shafts, seats, trim.
• Furnace Components: Trays, fixtures, radiant tube supports, retorts.
• Nuclear Industry: Control rod drive mechanisms, core components.
• Chemical Processing: Stirrers, spindles, agitators.

The workhorse nickel alloy bar stock for high-temperature and corrosive service components.