Incoloy 903

Aurico Alloys LLP supplies Incoloy 903 as sheet, plate and round bar, from Mumbai, India, with EN 10204 3.1 mill test certificates.

Incoloy® 903 (UNS N19903) is a controlled-expansion superalloy — nickel 36-40%, cobalt 13-17%, niobium 2.40-3.50% and titanium 1.00-1.85% on an iron balance. It combines low thermal expansion with a near-constant modulus across its working range, which is what gas turbine sealing and casing hardware is chosen for.

Key Properties

Low, controlled thermal expansion with a near-constant modulus — the property the grade exists for.
Nickel 36-40%, cobalt 13-17%, niobium 2.40-3.50%, titanium 1.00-1.85%, iron balance.
Age-hardenable, with aluminium 0.30-1.15%.
No ASTM standard is published for it. Special Metals supplies it to its own specification, which is what the specification table below records as mill.

Applications

Gas turbine casings and seal rings
Shafts and housings needing dimensional stability
Rings and spacers where clearance must hold with temperature

Available Forms

Equivalent Grades & Standards

Equivalent designations and physical constants for Incoloy 903
Property	Value
UNS number	N19903
Werkstoff / EN number	—
EN designation	—
Density	8.25 g/cm³
Melting range	1318-1393 °C
Curie temperature (age-hardened)	416-471 °C

Identifiers and physical constants for Incoloy 903. A dash means no such designation is published for this grade.

Specifications by Product Form

Incoloy 903 (N19903) is supplied to a different standard in each form. Quote the one that matches the product you are ordering.

Product form	Specification
Plate, sheet and strip	Mill specification
Rod and bar	Mill specification