SS309 · ISO 4955
SS309 is presented here as X18CrNi23-13 (4833-309-08-I) under ISO 4955. Heat-resistant steels and alloys for flat products used in elevated-temperature environments.
X18CrNi23-13
Designation: 4833-309-08-I
Data edition: ISO 4955:2016
SS309 4833-309-08-I
SS309 is presented here as X18CrNi23-13 (4833-309-08-I) under ISO 4955. Heat-resistant steels and alloys for flat products used in elevated-temperature environments.
Selected Table 2 compositions and Table 6 flat-product requirements. The exact ISO designations control these rows; the website material names are navigation references.
Related grades
3 material references with ISO 4955 data.
SS309 properties
Select a table to compare requirements.
| Element | Mass % |
|---|---|
| C | ≤0.20 |
| Si | ≤1.00 |
| Mn | ≤2.00 |
| P | ≤0.045 |
| S | ≤0.030 |
| Cr | 22.0–24.0 |
| Ni | 12.0–15.0 |
| Mo | — |
| N | ≤0.10 |
| Other elements | — |
Composition in mass %. ≤ denotes a maximum; ≥ denotes a minimum; paired values are ranges. — means no numerical limit is provided in the cited data, not zero.
| Form | Thickness (mm) | Condition | Test direction | Rp0.2 (MPa) | Rp1.0 min (MPa) | Rm (MPa) | A80 min (%) | A min (%) | Other requirements |
|---|---|---|---|---|---|---|---|---|---|
| Flat products | 0.5–75 | +AT | Transverse | 210 | 250 | 500–700 | 33 | 35 | HB ≤192 |
Room-temperature properties for the stated product form and condition. Proof strengths and elongation are minima unless a range is shown. A80 uses an 80 mm gauge length below 3 mm thickness; A uses 5.65√S₀ from 3 mm thickness. +AT means solution annealed.