Inconel 625
Solid-solution Ni-Cr-Mo superalloy. Stable to 980 °C, immune to seawater SCC.
Inconel 625 is a Ni-Cr-Mo solid-solution-strengthened superalloy. Outstanding crevice and pitting resistance in seawater, marine, and chemical service. Stable structure to ~980 °C with high creep strength. Welds readily without post-weld heat treatment.
Equivalent Designations
| Standard | Designation |
|---|---|
| UNS | N06625 |
| Werkstoff Nr. | 2.4856 |
| JIS | NCF 625 |
| BS | NA 21 |
| EN | NiCr22Mo9Nb |
Standards
ASTM B446 / ASME SB446 (bar, rod, wire, forgings)ASTM B443 (sheet/plate/strip)ASTM B704 / B705 (welded tube / pipe)
Chemical Composition (% by mass)
| Ni | 58.0 min |
| Cr | 20.0–23.0 |
| Mo | 8.0–10.0 |
| Fe | 5.0 max |
| Co | 1.0 max |
| Cu | 1.0 max |
| Mn | 0.50 max |
| Si | 0.50 max |
| C | 0.10 max |
| Al | 0.40 max |
| Ti | 0.40 max |
| Nb (+ Ta) | 3.15–4.15 |
| P | 0.015 max |
| S | 0.015 max |
Mechanical Properties
| Tensile Strength | 930 MPa (135 000 psi) |
| Yield Strength (0.2%) | 517 MPa (75 000 psi) |
| Elongation | 42.5 % |
Physical Properties
| Density | 8.4 g/cm³ |
| Melting Point | 1290–1350 °C |
Available Forms & Sizes
| Form | Size Range | Notes |
|---|---|---|
| Round Bar | Ø5 mm to Ø500 mm | Tolerance H8/H9/H10/H11 |
| Sheet / Plate | 0.5 mm to 100 mm thick × widths up to 2500 mm | — |
| Pipe / Tube | Seamless OD 6 to 350 mm; welded up to 1200 mm OD | — |
Finishes Available
Use Cases
Marine propulsion shafts, pump impellers, bellows, seawater fasteners
Outstanding crevice & SCC resistance in seawater.
Chemical processing
Heat exchangers in concentrated nitric/sulfuric/phosphoric acid mixtures, chlorine handling.
Aerospace exhaust
Engine nacelle skins, expansion joints, thrust reverser doors. Stable to ~980 °C.
Subsea oil & gas
Wellhead components, completion hardware, downhole tools (NACE MR0175 compliant).
Design Notes
- Welding: ERNiCrMo-3 matching filler. No post-weld heat treatment required for most service.
- Thick plate (>6 mm) rarely stocked domestically. Expect 10–14 day import lead times for thick plate (Constellium, ATI, Special Metals, Haynes International).
Indian Sourcing
Limited Indian stock — most Inconel is imported. Tikshara consolidates orders to reduce per-kg cost for low-volume buyers.