S355 grade materials are a low carbon structural steel with good weldability , which means that non-preheated welding is generally suitable as long as the parts involved are not too large. The highest permissible level of carbon equivalent is in the range of 0.45 - 0.52 % depending on diameter .
S355 in cold drawn application is standardized in SS-EN 10277-2 . SS-designation is 2172. The minimum yield strength level foreseen for steel S355J2C varies depending on the diameter in the range of 490 - 375 MPa . The tensile strength range decreases and the minimum elongation allowed in a tensile test increases slightly as the bar diameter increases. Impact toughness is not guaranteed.
If the application requires the part to have a wear resistant surface, the S355 responds well to both surface hardening and nitriding . In addition, its strength can be increased by quenching and tempering , provided that the cooling is fast enough during curing (in water or polymer quenchers) .