ASTM B443
Ni-Cr-Mo-Nb alloy (UNS N06625) plate, sheet and strip
The product specification for Alloy 625 (UNS N06625) plate, sheet and strip, in Grade 1 (annealed) and Grade 2 (solution-annealed) conditions.
- Plate, sheet & strip
- ASME SB-443
- 1 grade supplied to it
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is ASTM B443?
ASTM B443 is the specification for Ni-Cr-Mo-Nb alloy plate, sheet and strip — principally Alloy 625 (UNS N06625). It offers two conditions: Grade 1 (annealed), which gives higher strength, and Grade 2 (solution annealed), preferred for high-temperature creep service. General requirements are in ASTM B906. ASME adopts it as SB-443.
ASTM B443 at a glance
| Alloy | UNS N06625 (Alloy 625, sold as Inconel 625) |
|---|---|
| Products | Plate, sheet and strip |
| Conditions | Grade 1 annealed · Grade 2 solution annealed |
| General requirements | ASTM B906 |
| ASME designation | SB-443 |
Alloy 625 to B443 — minimum properties
Check the edition and the grade on your order. Current standard verification pending. Numerical specification requirements are published only after the applicable current standard edition has been verified.
| Condition | Tensile, min | Yield 0.2%, min | Elongation, min |
|---|---|---|---|
| Grade 1 annealed — cold-rolled sheet & strip | Pending current standard text | Pending current standard text | Pending current standard text |
| Grade 1 annealed — hot-rolled plate & sheet | Pending current standard text | Pending current standard text | Pending current standard text |
| Grade 2 (solution annealed) | Pending current standard text | Pending current standard text | Pending current standard text |
Alloy 625 specifications by product
| Product | Specification |
|---|---|
| Sheet · plate | ASTM B443 |
| Pipe & tube | ASTM B444 (seamless) · ASTM B705 (welded) |
| Buttweld fittings | ASTM B366 WPNCMC |
| Flanges | ASTM B564 |
How to write ASTM B443 on a purchase order
Name the product, size, material specification and grade, the dimensional standard and the certificate. An example line:
Illustrative only — sizes, tests, inspection level and any project values come from your purchase specification.
ASTM B443 edition and verification status
Which edition we have confirmed, and what is still being checked before any numerical requirement is published here.
| Current edition (publisher listing) | B443-26 — checked 7 October 2026 |
|---|---|
| Full-text verification | In progress — numerical requirements are published here only after the current text has been reviewed |
| Edition on your order | The edition named in your purchase order or design code governs — confirm it with your enquiry |
What to know before ordering to ASTM B443
The points that decide whether material to ASTM B443 is accepted at inspection.
- Grade 1 is the usual choice for corrosion service up to about 600 °C; Grade 2 is for higher-temperature creep service.
- Specify the grade — the two have different minimum strengths.
- Pipe in the same alloy is B444 (seamless) or B705 (welded).
Grades and products we supply to ASTM B443
| Grade | Product | Designation on the certificate |
|---|---|---|
| Inconel 625 | Sheet · Plate · Coil | ASTM B443 |
How ASTM B443 fits into an order
A purchase order line is only complete when it names the material standard, the dimensional standard and the inspection document. Miss one and the mill, the inspector and the buyer can each read the order differently.
Standards used with ASTM B443
Same family
ASTM B443 — questions buyers ask
What is ASTM B443?
ASTM B443 is the specification for Ni-Cr-Mo-Nb alloy plate, sheet and strip — principally Alloy 625 (UNS N06625). It offers two conditions: Grade 1 (annealed), which gives higher strength, and Grade 2 (solution annealed), preferred for high-temperature creep service. General requirements are in ASTM B906. ASME adopts it as SB-443.
What is the difference between B443 Grade 1 and Grade 2?
Grade 1 is annealed and has higher minimum strength; Grade 2 is solution annealed, with a coarser grain that gives better creep-rupture strength above about 600 °C.
Does B443 cover Inconel 625?
Yes. Inconel 625 is a trade name for Alloy 625, UNS N06625, the main alloy in B443.
Which grades do you supply to ASTM B443?
Inconel 625 — see the table on this page for the exact product and designation.
What is the current edition of ASTM B443?
The publisher's listing checked on 7 October 2026 shows B443-26 as the current edition. The edition that governs an order is the one named in the purchase order or design code. Full-text review of the current edition is in progress, so numerical requirements are not published on this page yet.
Do you supply certificates to this standard?
Yes. Material is supplied with mill test certificates to EN 10204 3.1 showing the standard, grade and heat number; 3.2 with third-party inspection on request.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026