ISO 4624 pull-off adhesion strength - marine specs require ≥ 3 MPa for new-build coatings, ≥ 5 MPa for PSPC-qualified.
Formula
$$ \sigma = \frac{F}{A}, \quad A = \tfrac{\pi d^2}{4} $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $F$ | Pull force at failure | N | adhesion tester |
| $d$ | Dolly diameter | mm | standard 20 mm |
| $σ$ | Adhesion strength | MPa | result |
Sources
- ISO 4624 - Pull-off test for adhesion.