S275N steel under EN10111 standard which is Non-alloy steel for structural purposes. More information about S275N steel details, please see the following:
S275N steel specification:
Grade: S275N
Number: 1.0490
Standard: EN 10111
Classification: Non-alloy quality structural steel
S275N steel size:
S275N Round bar diameter : 1mm-2000mm
S275N Square bar size: 50mm * 50mm-600mm *600mm
S275N Plate steel/flat bar size: Thickness: 0.1mm-800mm Width: 10mm to 1500mm
S275N Tube/pipe size: OD: 6-219mm WT: 1-35 mm.
S275N Cold-rolled sheet: Thickness: 2-5mm Width:1000mm Length: 2000mm
S275N Hot-rolled sheet: Thickness:6-80mm Width: 210-610mm
Length: We can supply any length based on the customer's requirement.
S275N Chemical composition: 
C:≤ 0.18, Mn:0.5-1.5 ,S :≤0.025, P :≤0.03, Si :≤ 0.4 , Cu:≤0.30, Ni:≤ 0.30, V:≤0.05, Nb:≤ 0.05, Al:≥0.02
S275N Mechanical properties:
Tensile Strength σb(MPa) :370-510
Yield Strength σ0.2(MPa): ≥275(thickness under 16mm); ≥265 (thickness above16mm)
Elongation δ5(%): ≥ 24( in Transverse)
Notch Impact Energy: ≥ 31J(20 degree) ; ≥ 27J(0 degree);≥ 24J(-10 degree); ≥ 31J(-20 degree) 
Bebon International is a professional S275N steel exporter and a steel stockist in china.  If you want to get the S275N steel price, please do not hesitate to contact us. Any need in S275N Chemical Composition and Mechanical Properties, please feel free to contact us by email or calling to us.