A nickel-chromium-molybdenum-niobium grade, Alloy 625, commonly referred to as Inconel® 625, offers outstanding corrosion resistance and superb weldability.

The addition of niobium provides high strength without the need for heat treatment. NeoNickel also offers Alloy 625 sheet with a combination of low-cycle fatigue and deep drawing quality.

  • UNS Number: N06625
  • Werkstoff Number: 2.4856
  • ASTM: B443, B444, B446, B704, B705, B366, B751, B775, B829
  • AMS: 5599, 5666, 5837, 5879, 5869, 5581

Product availability

Coiled Weld Wire
Pipe (Seamless)
Pipe Fittings
Round Bar
Round Tube
Welding Wire

Chemical analysis



  • Aircraft ducting and exhaust systems
  • Engine thrust-reverser systems
  • Turbine shroud rings
  • Bellows, expansion joints
  • Gaskets and damper seals
  • Motorsport exhaust and clamps
  • Weld overlay and spacers for heat recovery systems
  • Furnace muffles
  • Valve seats and components

About Alloy 625

Alloy 625, commonly referred to as Inconel® 625, demonstrates an excellent combination of corrosion resistance and high strength. Due to the high nickel content, Inconel® Alloy 625 is immune to chloride-induced stress corrosion cracking. It also has good resistance to pitting and crevice corrosion.

NeoNickel offers Alloy 625 sheet certified to both UNS N06625, 625 LCF® and ATI 625 HP® (UNS N06626). The 625 sheet meets the low-cycle fatigue properties specified in UNS N06626 and is also produced and certified as DDQ (deep drawing quality).

Resulting from the alloy’s excellent thermal stability, Alloy 625/Inconel® 625 is the alloy of choice for weld overlay applications in the oil and gas/petrochemical and refineries markets.
To learn more about Alloy 625 contact us, or fill in our online quote form and we’ll get right back to you!

ATI 625 HP® is a registered trademark of ATI Allegheny.
625 LCF® is a registered trademark of Special Metals Corporation.

  • Density: 8.442 g/cm³
  • Melting Point: 1287-1348°C

Mechanical & Physical Properties

Mechanical & Physical Properties21°C204 °C316 °C427 °C538 °C649 °C760 °C871 °C
Ultimate Tensile Strength /Mpa992.9923.9910.1910.1896.3820.5537.8275.8
0.2% Yield Strength /MPa579.2455.1434.4420.6420.6413.7406.8268.9
Elongation %444542.545483459117
Coefficient of Thermal Expansion µm/m⁰C-13.113.313.71414.815.315.8
Thermal Conductivity /kcal/(hr.m.°C)8.510.712.213.51516.417.919.6
Modulus of Elasticity/ MPa2.071.931.931.861.791.651.59-

Typical Rupture Strength, Bar

Temperature, °C649°C704°C760°C
100 Hours, ksi593418
1,000 Hours, ksi432312
Proud members of the British Valve & Actuator AssociationProud members of the British Valve & Actuator Association