Alloy 625 - INCONEL® 625 – properties, applications and technical data
Alloy 625 is a nickel-chromium alloy with the addition of molybdenum and niobium. These additives give the material high mechanical strength and very good corrosion resistance without the need for the alloy to be hardened by heat treatment.
The material is often used in demanding environments in the offshore, energy and aerospace industries as well as in pollution control and chemical process equipment where both strength and corrosion resistance are crucial.
Properties of Alloy 625
Alloy 625 is known for its good resistance to both localized corrosion and general corrosion in many aggressive environments. The combination of nickel, chromium, molybdenum and niobium gives the material good resistance in chloride-containing environments as well as stable mechanical properties at elevated temperatures.
The material is often used in welded structures where both high strength and long service life in corrosive environments are required.
- Type: nickel-based superalloy
- Alloy: Ni-Cr-Mo-Nb
- Structure: nickel-based austenitic alloy
- Designations: Alloy 625, UNS N06625, W.Nr. 2.4856, INCONEL 625
- Typical composition: Ni balance, Cr ~20-23%, Mo ~8-10%, Nb ~3-4%, Fe ~5%
Advantages
- Very good corrosion resistance in many aggressive environments
- Good resistance to pitting and crevice corrosion
- High mechanical strength without heat treatment
- Stable properties at elevated temperatures
- Proven material in offshore, energy and aerospace industries
Limitations
- Higher material cost than standard stainless steels
- Should be used in applications where high corrosion resistance required
- Not necessary in environments where simpler alloys meet the requirements
Common product forms for Alloy 625
- Round bar
- Sheet and strip
- Pipe and fittings
- Forgings
- Welding consumables
Typical uses for Alloy 625
- Offshore equipment and marine systems
- Aerospace components
- Pollution control equipment
- Chemical process equipment
- Heat exchangers and reaction vessels
- High temperature components in energy systems
Compatible base materials
Alloy 625 is often used in welded structures where high corrosion resistance and good mechanical strength are required. The material can be welded with filler metals of the same alloy and is also used in dissimilar welding between nickel-based alloys and stainless steels.
- Alloy 625 / UNS N06625
- Alloy 600 and Alloy 601
- Alloy 800 / 800H / 800HT
- Alloy 825
- Alloy C276
- Nickel 200 and Nickel 201
- Austenitic stainless steels
- Duplex and superduplex stainless steels
- Carbon steels in dissimilar welding
Corrosion resistance
Alloy 625 offers very good resistance to a wide range of of corrosive media. The alloy is particularly resistant to chloride-containing environments and many chemical process environments.
The material is therefore often used in equipment operating in aggressive environments where long service life and operational reliability are important requirements.
Environments where Alloy 625 performs well
- Marine and offshore environments
- Chloride-containing solutions
- Chemical process environments
- High-temperature environments
Environments to avoid
- Applications where simpler and cheaper alloys are sufficient
- Environments where high corrosion resistance is not required
- Constructions where material costs must be kept low
Technical data
| Stretch limit (0.2%) |
~460 MPa |
| Tensile strength |
~830 MPa |
| Extension |
~30% |
| Density |
~8.4 g/cm³ |
| Melting interval |
~1290-1350 °C |
Recommended welding consumables are Alloy 625-based welding materials, such as welding wire of type Alloy 625 and welding electrodes such as INCONEL 112.
Contact us for price, availability and technical advice.
Supplier of Alloy 625 with certified quality
HARALD PIHL is one of Europe's largest suppliers of special alloys and nickel-based materials, including materials for demanding industrial applications.
With over 100 years of experience in the metal industry, we deliver materials with full traceability and certification according to EN 10204 3.1 / 3.2 as well as relevant ASTM, AMS and ISO standards.
Cutting, testing and quality assurance are carried out in-house to ensure the right tolerances and fast global delivery to technically demanding projects.
- Europe's largest stock of nickel and titanium alloys
- Special alloys from stock
- ASTM / AMS / ISO standards
- Top quality for safety-critical applications
- Fast global delivery
- Full material certification (EN 10204 3.1 / 3.2)
- Over 100 years in the metal industry
- Nickel and titanium experts
