Wire – Alloy 347 Stainless Steel

Wire – Alloy 347 Stainless Steel

Alloy 347 Stainless Steel

UNS N34700
W.Nr 1.4550


Annealing covers, High-temperature tempering equipment, Diesel and heavy-duty automotive exhaust, Firewalls, Stack liners, Boiler casings, Welded pressure vessels, Aircraft components, Bellows, Oil refinery equipment, Fasteners, Springs


Type 347 Stainless Steel is a stabilized austenitic stainless steel, similar to type 304, but alloyed with Niobium (Columbium) for use in applications involving continuous or intermittent service at 800-1500°F (427-816°C). 347 stainless has excellent resistance to oxidation, even surpassing that of 321 in strong oxidizing conditions. The alloy maintains resistance to intergranular corrosion, while also possessing good creep strength compared to other 300 series stainless steels. The alloy is strengthened only through cold work and can be fabricated, machined, and welded via most conventional processes.

Industries Supplied

Aerospace, Oil & Gas, Chemical Processing, Food Processing, Waste Treatment

Nominal Composition

C: 0.08 max
Mn: 2.0 max
Si: 1.00 max
P: 0.045 max
S: 0.030 max
Ni: 9.00 – 12.00
Cr: 17.0 – 19.0
Nb (Cb): 10*C – 1.0
N: 0.10 max
Fe: Bal min

Physical Properties

Density: 0.288 lb/in3, (7.96 g/cm3)

Modulus of Elasticity (E):
At 70°F (20°C): 28.0 x 103 ksi (193 GPa)

Modulus of Rigidity (G):
At 70°F (20°C): 11.2 x 103 ksi (78 GPa)

Coefficient of Expansion:
11.4 µin/in-°F (32-1500°F)
20.5 µm/m-°C (0-871°C)

Electrical Resistivity: 28.4 µohm-in, (72.0 µohm-cm)

Thermal Conductivity: 113 Btu-in/ft2-hr-°F (212°F), 16.3 W/m-°C (100°C)

Applicable Specifications

Wire & Bar: AMS 5674, 5646, ASTM A313, ASTM A580, NACE MR0175/ISO 15156

Typical Mechanical Properties

  • Annealed
    • Heat Treatment: 1750-2050°F (954-1121°C)
    • Tensile Strength: 80-110 ksi (552-758 MPa)
    • Suggested Operating Conditions: Up to 1500°F (816°C)
  • Spring
    • Heat Treatment: Stress Relieve 600-900°F (316-482°C)
    • Tensile Strength: 200 ksi min (1379 MPa)
    • Suggested Operating Conditions: Up to 550°F (228°C)

For further information Contact:

Contact Us
Phone: 1 847 695 1900
Elgiloy Specialty Metals – Wire Products
356 N.Cross Street
Sycamore, IL 60178 USA

Limitation of Liability and Disclaimer of Warranty:
• The content in these data sheets is provided primarily by third-party melting mills and is provided for reference only. It is not intended for engineering or design.
• Applications may be discussed, however, Elgiloy Specialty Metals, a Division of Combined Metals Company LLC, does not recommend or endorse any material for any particular end use or application.
• The data included in this data sheet are typical values and may vary.
• Elgiloy Specialty Metals, a Division of Combined Metals Company LLC, makes no representations or warranties, express or implied, as to the accuracy, completeness, condition, suitability, performance, fitness for a particular purpose, or merchantability of any information contained in any data sheet.
• In no event will Elgiloy Specialty Metals, a Division of Combined Metals Company LLC, be liable for any damages whatsoever arising from the use of the information included in the data sheets.