Difference between S275NL and S275N steel plate - Knowledge

S275N and S275NL are fine-grain structural steels under EN 10025-3, sharing yield strength (275 MPa) but differing in impact toughness: S275N is tested at -20°C (47J), while S275NL offers superior performance, tested at -50°C (27J), making it better for cold climates, with S275NL also having tighter limits on carbon and sulfur for enhanced weldability.

S275N and S275NL both are normalized fine-grain structural steels designed for welded constructions, offering excellent weldability and strength.

However, S275NL provides enhanced low-temperature toughness compared to S275N, making it suitable for harsher environments.

Our plates are delivered in normalized or normalized rolled conditions to ensure superior performance.

S275N and S275NL are low-alloy, fine-grain structural steels under EN 10025-3 (designations 1.0490 and 1.0491, respectively). The "S" indicates structural steel, "275" denotes a minimum yield strength of 275 MPa, "N" means normalized delivery, and the "L" in S275NL signifies extended low-temperature impact testing.

While they share identical yield and tensile strength requirements, the key distinction lies in Charpy V-notch impact energy testing: S275N at -20°C versus S275NL at -50°C. This makes S275NL ideal for arctic or sub-zero applications, whereas S275N suffices for moderate climates. Compared to higher grades like en 10025 3 s355n normalized structural steel plate, both offer cost-effective options for weldable structures.

Chemical Composition Differences

Element	Symbol	S275N Min (%)	S275N Max (%)	S275NL Min (%)	S275NL Max (%)
Carbon	C	-	0.18	-	0.16
Silicon	Si	-	0.40	-	0.40
Manganese	Mn	0.50	1.50	0.50	1.50
Nickel	Ni	-	0.30	-	0.30
Phosphorus	P	-	0.030	-	0.025
Sulfur	S	-	0.025	-	0.020
Chromium	Cr	-	0.30	-	0.30
Molybdenum	Mo	-	0.10	-	0.10
Vanadium	V	-	0.05	-	0.05
Nitrogen	N	-	0.015	-	0.015
Niobium	Nb	-	0.05	-	0.05
Titanium	Ti	-	0.05	-	0.05
Aluminum	Al	0.02	-	0.02	-
Copper	Cu	-	0.55	-	0.55
CEV	-	-	0.40	-	0.40

Mechanical Properties Comparison

Nominal Thickness (mm)	Yield Strength ReH Min (MPa) - Both	Tensile Strength Rm (MPa) - Both	Elongation A Min (%) - Both	Charpy KV Longitudinal Min (J) S275N at -20°C	Charpy KV Longitudinal Min (J) S275NL at -50°C	Charpy KV Transverse Min (J) S275N at -20°C	Charpy KV Transverse Min (J) S275NL at -50°C
≤ 16	275	370–510	24	47	27	31	16
16 < t ≤ 40	265	370–510	24	47	27	31	16
40 < t ≤ 63	255	370–510	24	47	27	31	16
63 < t ≤ 80	245	370–510	23	47	27	31	16
80 < t ≤ 100	235	370–510	23	47	27	31	16
100 < t ≤ 150	225	350–480	23	47	27	31	16
150 < t ≤ 200	215	350–480	23	47	27	31	16
200 < t ≤ 250	205	350–480	23	47	27	31	16

S275N and S275NL share identical strength (205–275 MPa yield) and weldability under EN 10025-3 but differ primarily in impact toughness: -20°C for S275N versus -50°C for S275NL, with S275NL's tighter chemistry enhancing cold ductility. Select S275N for moderate conditions and S275NL for extreme cold, ensuring optimal safety and performance in structural applications.