S355 steel plate is a non-alloy European standard (EN 10025-2) structural steel, most commonly used after S235 where more strength is needed. S355 steel plate got great weldability and machinability, let us see more mechanical details of S355 steel plate.
For the S355 steel plate, S - stands for structural steel，355 - stands for minimum yield strength.
Normally S355 steel plate will have following variation based on impact strength at different temperatures, as steel become more brittle when temperature drops.
S355 steel plate is named based on it's minimum yield strength of 355 Mpa (N/mm2), However the yield strength reduces when you go up in thickness above 16 mm for flat products & hollow sections.
Here is the S355 steel plate yield strength based on different thickness.
Up to 16 mm - 355 Mpa
16 mm < t ≤ 40 mm - 345 Mpa
40 mm < t ≤ 63 mm - 335 Mpa
63 mm < t ≤ 80 mm - 325 Mpa
80 mm < t ≤ 100 mm - 315 Mpa
100 mm < t ≤ 150 mm - 295 Mpa
