Difference between S275N and S355N steel plate

Dec 29, 2025 Zanechat vzkaz

S275N and S355N are European standard (EN 10025-3) fine-grain structural steels, differentiated mainly by yield strength (S275 has ~275 MPa, S355 has ~355 MPa), with S355 offering higher strength for heavy-duty applications like bridges and cranes, while S275 serves general structures, both prized for good weldability and low-temperature toughness due to the 'N' (Normalized) designation, making them versatile for demanding projects.

S275N and S355N are both normalized fine-grain structural steel plates designed for welded constructions requiring enhanced toughness at low temperatures down to -20℃.

S275N offers a minimum yield strength of 275 MPa, while S355N provides higher strength at 355 MPa, making S355N more suitable for heavier loads than S275N.

	S275N Max (%)	S355N Max (%)
C	0.20	0.20
	0.40	0.50
	0.80–1.60	0.90–1.60
P	0.035	0.025
S	0.030	0.020
	0.30	0.30
	0.10	0.10
V	0.05	0.12
N	0.012	0.015
	0.050	0.050
	0.050	0.050
	>=0.020	>=0.020
	0.35	0.55
-	0.40	0.43

	Yield ReH Min (MPa) S275N	Yield ReH Min (MPa) S355N	Tensile Rm (MPa) S275N	Tensile Rm (MPa) S355N		Charpy KV Longitudinal Min (J) at -20℃ Both
<= 16	275	355	370–530	470–630	23	47
16 < t <= 40	265	345	370–530	470–630	23	47
40 < t <= 63	255	335	370–530	470–630	23	47
63 < t <= 80	245	325	370–530	470–630	22	47
80 < t <= 100	235	315	370–530	470–630	22	47
100 < t <= 150	225	295	350–510	450–600	22	47
150 < t <= 200	215	285	350–510	450–600	22	47
200 < t <= 250	195	265	350–510	450–600	22	47

Heat Treatment: Both normalized (+N: 880–920℃ austenitize, air cool) for fine-grain.
Welding: Low CEV (0.40/0.43), no preheat <=40 mm; S355N may need more care for thicker sections.
Follow EN 1011-2. Gangsteel optimizes for both.