ASTM B425 Specification

This specification2 covers nickel-iron-chromiummolybdenum-copper alloy (UNS N08825 and UNS N08221)* in the form of hot-finished and cold-drawn rounds, squares, hexagons, and rectangles. The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

Chemical Composition

Element UNS N08825 UNS N08221
Nickel 38.0-46.0 39.0-46.0
Chromium 19.5-23.5
20.0-22.0
lronA 22.0 min balance
Manganese 1.0 max 1.0 max
Carbon 0.05 max 0.025 max
Copper 1.5-3.0 1.5-3.0
Silicon 0.5 max 0.5 max
Sulfur 0.03 max 0.03 max
Aluminum 0.2 max 0.2 max
Titanium 0.6-1.2 0.6-1.0
Molybdenum 2.5-3.5 5.0-6.5
Note:

A. Element shall be determined arithmetically by difference.

Mechanical Properties

Alloy Condition Tensile Strength min, ksi (MPa) Yield Strength 0.2 % offset, min, ksi (MPa) Elongation in 2 in. or 50 mm or 4D, min,%
UNS N08825 Annealed: Hot-finished, cold–drawn
85 (586) 35 (241) 30A
Forging Quality: B B B
UNS N08221 All sizes annealed 79 (544) 34 (235) 30
Note:

A. Not applicable to diameters or cross sections under 3⁄32 in. (2.4 mm).
B. Forging quality is furnished to chemical requirements and surface inspection only. No tensile properties are required.