ASTM B444 INCONEL 625 U BEND TUBE (UNS NO6625 , DIN 2.4856) HEAT
EXCHANGER APPLICATION
INCONEL 625 characteristics:
- 1. High creep-rupture strength
- 2. Oxidation resistant to 1800° F
- 3. Seawater pitting and crevice corrosion resistant
- 4. Immune to chloride ion stress corrosion cracking
- 5. Non-magnetic
Inconel 625 application:
- 1. Aircraft ducting systems
- 2. Aerospace
- 3. Jet engine exhaust systems
- 4. Engine thrust-reverser systems
- 5. Specialized seawater equipment
- 6. Chemical process equipment
Overview
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. Some typical applications Inconel 625 is used in
are chemical processing, aerospace and marine engineering,
pollution-control equipment, and nuclear reactors.
Chemical Composition
Cr | Ni | Mo | Co + Nb | Ta | Al | Ti | C | Fe | Mn | Si | P | S |
|---|
| 20.00-30.00 | Remainder | 8.0-10.0 | 1.0 max | 3.15-4.15 | .40 max | .40 max | .10 max | 5.0 max | .50 max | .50 max | .015 max | .015 max |
Mechanical Properties
Temp° F | Tensile (psi) | .2% Yield (psi) | Elongation in 2"(%) |
|---|
| 70 | 144,000 | 84,000 | 44 |
| 400 | 134,000 | 66,000 | 45 |
| 600 | 132,000 | 63,000 | 42.5 |
| 800 | 131,500 | 61,000 | 45 |
| 1000 | 130,000 | 60,500 | 48 |
| 1200 | 119,000 | 60,000 | 34 |
| 1400 | 78,000 | 58,500 | 59 |
| 1600 | 40,000 | 39,000 | 117 |
Specifications
Pipe Smls | Pipe Welded | Tube Smls | Tube Welded | Sheet/Plate | Bar | Forging | Fitting | Wire |
|---|
| B444 | B705 | B444 | B704 | B443 | B446 | - | - | - |
Fabrication with Inconel 625
Alloy 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.
