Property Class 8.8 Steel (ISO 898-1 property class 8.8) is the workhorse medium-carbon alloy class for structural joints. When pan head screws are specified in this grade, the dimensions remain per ISO 1207 / ISO 7045 / DIN 7985; the material determines corrosion behavior (requires plating (zinc) for corrosion protection) and the service temperature range (commonly limited to approx. +300 °C; confirm against the coating and the load). Both are covered below with the size table.
Why Choose Property Class 8.8 Steel for Pan Head Screws
The workhorse medium-carbon alloy class for structural joints. For pan head screws, this matters when requires plating (zinc) for corrosion protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 898-1 property class 8.8 |
|---|---|
| Magnetic response | Magnetic |
| Service temperature | commonly limited to approx. +300 °C; confirm against the coating and the load |
| Corrosion characteristic | Requires plating (zinc) for corrosion protection |
Galvanic & Galling Considerations
For pan head screws in steel, the dominant compatibility issue is hydrogen embrittlement at high property classes (10.9 and above) when electroplated. Plating must be followed by an appropriate baking treatment, or a non-electroplated finish (mechanical zinc, zinc flake) should be substituted.
Comparable Grades
For Pan Head Screws, class 10.9 or 12.9 is the comparable strength step. Move up when the joint preload approaches the proof load of the current class; move down when the joint is over-specified. For corrosion-critical service, switch to stainless A2 or A4.
Sizes of Pan Head Screws Available in Property Class 8.8 Steel
| Size | Pitch (mm) | Head diameter dk (mm) | Head height k (mm) | Cross recess | Reference standard |
|---|---|---|---|---|---|
| M1 | 0.25 | 2.0 | 0.8 | PH0 | ISO 1207 / ISO 7045 / DIN 7985 |
| M1.2 | 0.25 | 2.3 | 0.9 | PH0 | ISO 1207 / ISO 7045 / DIN 7985 |
| M1.4 | 0.3 | 2.6 | 1.0 | PH0 | ISO 1207 / ISO 7045 / DIN 7985 |
| M1.6 | 0.35 | 3.0 | 1.0 | PH0 | ISO 1207 / ISO 7045 / DIN 7985 |
| M2 | 0.4 | 3.8 | 1.3 | PH1 | ISO 1207 / ISO 7045 / DIN 7985 |
| M2.5 | 0.45 | 4.7 | 1.5 | PH1 | ISO 1207 / ISO 7045 / DIN 7985 |
| M3 | 0.5 | 5.6 | 1.8 | PH1 | ISO 1207 / ISO 7045 / DIN 7985 |
| M3.5 | 0.6 | 6.5 | 2.1 | PH2 | ISO 1207 / ISO 7045 / DIN 7985 |
| M4 | 0.7 | 8.0 | 2.4 | PH2 | ISO 1207 / ISO 7045 / DIN 7985 |
| M5 | 0.8 | 9.5 | 3.0 | PH2 | ISO 1207 / ISO 7045 / DIN 7985 |
| M6 | 1.0 | 12.0 | 3.6 | PH3 | ISO 1207 / ISO 7045 / DIN 7985 |
| M8 | 1.25 | 16.0 | 4.8 | PH3 | ISO 1207 / ISO 7045 / DIN 7985 |
| M10 | 1.5 | 20.0 | 6.0 | PH4 | ISO 1207 / ISO 7045 / DIN 7985 |

