VDM® Alloy 625 (2.4856/N06625)

VDM® Alloy 625 is a nickel-chromium-molybdenum-niobium alloy with excellent resistance to a variety of corrosive media.

Characteristics of VDM® 625

VDM® Alloy 625 (2.4856/N06625) in the soft annealed condition (grade 1) is characterized by:

Exceptional resistance to pitting, crevice corrosion, erosion and intergranular corrosion
Immunity to chloride-induced stress corrosion cracking
Good resistance to mineral acids such as nitric, phosphoric, sulfuric and hydrochloric acid
Good resistance to alkalis and organic acids
Good mechanical properties

Applications of VDM® Alloy 625

The soft annealed version of VDM® Alloy 625 (grade 1) is used in the oil and gas industry, the chemical process industry, marine engineering and environmental engineering. Typical applications include:

Equipment for the production of super phosphoric acid
Plants for the treatment of radioactive waste
Production pipe systems and linings of risers in oil production
Offshore industry and seawater exposed equipment
Sea water piping in shipbuilding
Stress corrosion cracking resistant compensators
Furnace linings
pipes in concentrating solar power (CSP) plants

For high temperature applications up to 1,000 °C (1,832 °F), the solution treated variant (grade 2) acc. to ASME Code for Pressure Vessels is used. Typical applications include:

Flaring systems in refineries and offshore platforms
Recuperators and compensators for hot exhaust gases

VDM® FM 625 is used as a matching filler metal for corrosion-resistant coatings of less resistant steels (overlay welding). Typical applications include: