ASTM A203 Grade F: thickness-split official minima in the 3.50% nickel family
Gangsteel produces and exports ASTM A203 Grade F nickel-alloy plate. Grade F is the only A203 grade whose official public Scope splits the strength minima by thickness. It is not a normalized A203 Grade E substitute, even though both belong to the 3.50% nominal-nickel family.
Official strength depends on the ordered thickness
A203/A203M-23 is the current public edition. Official Scope gives Grade F nominal nickel of 3.50% and thickness-split minima: for 2 in. [50 mm] and under, yield 55 ksi [380 MPa] and tensile 80 ksi [550 MPa]; over 2 in. [50 mm], yield 50 ksi [345 MPa] and tensile 75 ksi [515 MPa]. These are minima, not a complete tensile table. The official abstract requires killed, fine-grain steel and says Grades A, B, D and E shall be normalized as required; that official sentence does not name Grade F.
| Requirement | Official public Scope, ≤2 in. [50 mm] | Official public Scope, over 2 in. [50 mm] | Dated compilation, ≤50 mm | Dated compilation, >50 mm |
|---|---|---|---|---|
| Tensile min, ksi [MPa] | 80 [550] | 75 [515] | 80 [550] | 75 [515] |
| Tensile max, ksi [MPa] | 100 [690] | 95 [655] | ||
| Yield min, ksi [MPa] | 55 [380] | 50 [345] | 55 [380] | 50 [345] |
| Elongation min, 2 in. [50 mm], % | 20 | 20 | ||
| Elongation min, 8 in. [200 mm], % |
The Grade F compilation dated 14 September 2026 therefore gives tensile strength 80–100 ksi [550–690 MPa] at ≤50 mm and 75–95 ksi [515–655 MPa] over 50 mm. Official upper tensile and all official elongation cells stay blank. The compilation prints only the 2 in. elongation, 20% at both bands; the 8 in. cell is left blank because no independently confirmed value is available. Gauge length is not a thickness band. Inch-pound and SI systems are independent. Designers must apply the correct official line for the ordered thickness.
Delivery condition: official clause unread, compilation route labelled
The official public Scope and official abstract do not publish the Grade F heat-treatment clause. The dated compilation describes a mandatory austenitize, water-quench and temper route, with a temper of not less than 595 °C (1100 °F) for not less than 1/2 hour, and says normalizing alone does not meet Grade F. Those figures and that wording are labelled compilation notes to confirm in the ordered edition; they are not official Scope values. Agree the contractual delivery route before production.
Grade F chemistry: confirmed on this grade’s own page
Official nominal nickel is 3.50%. The chemistry below was independently confirmed on the dated Grade F compilation, not copied from Grade E or Grade B, and not taken from a live table headed “Element A203 Grade A”. These tables are not official Table 1.
| Plate thickness | Heat C max, % | Heat Mn max, % | Product Mn max, % |
|---|---|---|---|
| ≤50 mm | 0.20 | 0.70 | 0.78 |
| >50–100 mm | 0.23 | 0.80 | 0.88 |
| Element | Heat analysis, % | Product analysis, % | Current official table |
|---|---|---|---|
| Si | 0.15–0.40 | 0.13–0.45 | |
| Ni | 3.25–3.75 | 3.18–3.82 | |
| P | 0.025 max | ||
| S | 0.025 max | ||
| C | See thickness table |
The two heat-carbon maxima, 0.20% and 0.23% through 100 mm, coincide with the Grade E compilation but were read on the Grade F page itself. No >100 mm carbon row is printed, and none is filled from another grade. Manganese values are separate maxima, not a range. Product C, P and S numeric cells stay blank pending the A20/A203 product check and the order. The 3.25–3.75% heat and 3.18–3.82% product nickel bands are labelled compilation figures beside the official 3.50% nominal content.
Equivalent materials: do not replace a Grade F order with a normalized grade
Grade F must be reviewed against its thickness-split official minima, its 3.50% nickel identity and the agreed delivery condition. A higher-nickel or higher-strength look-alike is not an automatic substitute.
| Material considered | What to compare | Direct substitute? |
|---|---|---|
| A203 Grade E | Same 3.50% nominal nickel family, but official minima are lower (40 / 70 ksi) and are not thickness-split. Official public text requires Grades A, B, D and E to be normalized as required; that sentence does not name Grade F. | No. Do not treat a normalized Grade E order as Grade F. |
| A203 Grade D | Same nickel family, with still lower official minima (37 / 65 ksi) and no official thickness split. | No. |
| A203 Grade B | A 2.25% nickel grade whose official minima match Grade E, not Grade F. | No. |
| A203 Grade A | A 2.25% nickel grade with Grade D’s official minima. | No. |
| SA-203 Grade F / ASME Code acceptance | Governing Code, certificate designation, approved delivery condition and tests must satisfy the order. | Not automatically. ASTM and ASME are not interchangeable in either direction. |
Related plate choices
A203 Grade E — the normalized 3.50% nickel grade at lower official minima; A203 Grade D — the lower-strength 3.50% nickel designation; A203 Grade B and A203 Grade A for the 2.25% nickel family. These links are navigation, not substitution approval or technical sources.
Questions before releasing a Grade F order
Which official strength line applies to a 50 mm plate?
Use the official “2 in. [50 mm] and under” minima for that thickness, and confirm the unit system of the order. Do not average the two official rows.
Does a blank 8 in. elongation cell mean zero?
No. An independently confirmed official or compilation value is unavailable; none is inferred from the 2 in. result.
Can we supply Grade F in the normalized condition used for Grade E?
Not on the basis of this page. The official heat-treatment clause was not published on the public Scope, and the dated compilation treats quench-and-temper as the Grade F route. Confirm the contractual condition in the ordered edition.
Is 100 mm the official thickness cap?
No. Official Scope limits thickness by composition capability. A compilation supply range is not an official maximum.
Are the 595 °C and 1100 °F temper figures official?
No. They appear only in the dated compilation, together with the 1/2 hour minimum hold. Confirm them in the ordered specification. Paid ASTM/ASME full texts were not read.
Confirm your Grade F production and export requirement
Send the Grade F plate schedule to Gangsteel, identifying edition, A203/A203M unit system, thickness so the correct official strength line can be reviewed, quantity, agreed delivery condition, tests, inspection documents and destination.