A204 Gr.B vs P265GH
These two grades are listed as equivalents of each other: their chemistry windows overlap and they serve the same applications. They are not always identical — check the differences below before substituting, especially in certified designs.
A204 Gr.B
Structural & HSLA Steel
ASTM A204 Grade B is a molybdenum-alloy (0.5Mo) pressure-vessel plate whose Mo addition lifts elevated-temperature strength above the plain-carbon A516 family. The carbon limit rises in steps with plate thickness in the standard; the value shown is for plate up to 25 mm.
Standards: AISI A204 Gr.B
P265GH
Structural & HSLA Steel
P265GH is the EN 10028-2 workhorse pressure-vessel steel for European boiler and vessel fabrication — the normalized C-Mn grade that sits a step below P355GH in strength. Its GH suffix marks it as proven for high-temperature (elevated-temperature) service.
Standards: DIN 1.0425 (P265GH) · AISI A516 Gr.70 (near) · JIS SGV410 (near) · GB Q245R (near)
Chemical composition compared (%)
| Element | A204 Gr.B | P265GH |
|---|---|---|
| C | ≤0.20 (≤25 mm) | ≤0.20 |
| Si | 0.15–0.40 | ≤0.40 |
| Mn | ≤0.90 | 0.80–1.40 |
| P | ≤0.025 | ≤0.025 |
| S | ≤0.025 | ≤0.010 |
| Mo | 0.45–0.60 | ≤0.08 |
| Cr | — | ≤0.30 |
| Cu | — | ≤0.30 |
| Ni | — | ≤0.30 |
Properties compared
| Property | A204 Gr.B | P265GH |
|---|---|---|
| Yield strength | ≥275 MPa | ≥265 MPa |
| Tensile strength | 485–620 MPa | 410–530 MPa |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
| Service | — | Elevated-temperature pressure equipment (EN 10028-2) |
Sourcing either grade?
Nasteel stocks both families from Shenzhen with EN 10204 3.1 mill certificates by heat number.
Ask for a quotationSee full data sheets: A204 Gr.B · P265GH. Substitution decisions for certified parts stay with the design authority.