S275 grade steel is a readily weldable low carbon manganese steel with good impact resistance (including in sub-zero temperatures).
This material is commonly supplied in the untreated or normalised condition and is available in several variations (denoted by additional letters and/or digits), which offer slight modifications of chemical composition and mechanical properties.
Machinability of this material is similar to that of mild steel.
S275 engineering bar available from Hillfoot
(*differs with section thickness and grade variation)