General Engineering Quality Steel – Colour: Blue
Bright: BS 970: Part 3: 1991: 080A15
Imperial Hexagon (inches)
.562, .687, .750, .820, .875, .937, 1.000, 1.100, 1.125, 1.500, 1.670, 1.860, 1.875, 2.220 & 3.150
Lengths – Standard bar lengths are 3/3.5 metres
Mild steel is a generic term applied to low carbon steels that do not contain any alloying elements and where the carbon content does not exceed 0.25%. this covers a wide range of specifications and forms of steel.
For mechanical engineering applications mild steel is used for parts that are not subject to high stress. Depending on the analysis, section and form of supply the tensile strength generally falls in the broad range of 350/550 N/mm². When supplied in the bright cold drawn condition higher figures are obtainable, especially on small diameters.
In earlier editions of BS 970 up to 1970 the most popular specification for bright mild steel was En3B, a loose specification with an analysis of 0.25% carbon max. and 1.00% manganese max. When the six digit system was introduced En3B was omitted and replaced by steels with a tighter chemical analysis, the harmonization of European steel standards requiring revisions to BS 970 has led to further changes. For clarification, the following mild steels may safely be specified for general mechanical engineering use.
Also available as:
USAMILD – Carbon Steel – Colour: Blue/Red
Bright: BS 970: 1955: En3B, BS 970: Part 3: 1991: 070M20
USACASE – Carbon Case- Hardening Steel – Colour: Red
Bright: BS 970: Part 3: 1991: 080M15, BS 970: 1955: En32