UNS Number N06625

Inconel 625 is a corrosion and oxidation resistant nickel alloy that is used both for its high strength and outstanding aqueous corrosion resistance. Its outstanding strength and toughness is due to the addition of niobium which acts with the molybdenum to stiffen the alloy’s matrix. Alloy 625 has excellent fatigue strength and stress-corrosion cracking resistance to chloride ions. This nickel alloy has excellent weldability and is frequently used to weld AL-6XN. This alloy resists a wide range of severely corrosive environments and is especially resistant to pitting and crevice corrosion.

Available Forms of Inconel 625 at Rooplaxmi Steels:

•           Sheet
•           Plate
•           Bar
•           Pipe & Tube (welded & seamless)
•           Wire

Characteristics of Inconel 625:

•           High creep-rupture strength
•           Oxidation resistant to 1800° F
•           Seawater pitting and crevice corrosion resistant
•           Immune to chloride ion stress corrosion cracking
•           Non-magnetic

Inconel 625 Chemical Composition, %:

Cr	Ni	Mo	Co+Nb	Ta	Al	Ti	C
20.0-30.0	Balance	8.0-10.0	1.0 max	3.15-4.15	0.40 max	0.40 max	0.10 max

Fe	Mn	Si	P	S
5.0 max	0.50 max	0.50 max	0.015 max	0.015 max

 

Application of Inconel 625:

•           Aircraft ducting systems
•           Aerospace
•           Jet engine exhaust systems
•           Engine thrust-reverser systems
•           Specialized seawater equipment
•           Chemical process equipment

Machining and Fabrication with Inconel 625:

Inconel 625 has excellent forming and welding characteristics. It may be forged or hot worked providing temperature is maintained in the range of about 1800-2150° F. Ideally, to control grain size, finish hot working operations should be performed at the lower end of the temperature range. Because of its good ductility, alloy 625 is also readily formed by cold working. However, the alloy does work-harden rapidly so intermediate annealing treatments may be needed for complex component forming operations. In order to restore the best balance of properties, all hot or cold worked parts should be annealed and rapidly cooled. This nickel alloy can be welded by both manual and automatic welding methods, including gas tungsten arc, gas metal arc, electron beam and resistance welding. It exhibits good restraint welding characteristics.

Inconel 625 ASTM Specification:

Pipe Smls	Pipe Welded	Tube Smls	Tube Welded	Sheet / Plate	Bar
B444	B705	B444	B704	B443	B446

Welding Wire Designations:
AWS A5.14 – ERNiCrMo3

 

Mechanical Properties of Inconel 625:

Representative Tensile Properties, Bar, 1800°F Anneal

Temp° F	Tensile (psi)	0.2% Yield (psi)	Elongation in 2” (%)
70	144000	84000	44
400	134000	66000	45
600	132000	63000	42.5
800	131500	61000	45
1000	130000	60500	48
1200	119000	6000	34
1400	78000	58500	59
1600	40000	39000	117