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EN3B is a general engineering steel which is suitable in applications where heavy stresses and heat treatment are not involved. It is a bright drawn / turned mild steel with good machinability but poor hardenability, and is used in a variety of general engineering applications.
The term Mild Steel applies to all low carbon steel that does not contain any alloying elements in its makeup and has a carbon content that does not exceed 0.25%. The term “Mild” is used to cover a wide range of specifications and forms for a variety of Steel.
Mild Steel is used in mechanical engineering applications for parts that will not be subject to high stress.
When in its bright cold drawn condition the Steel is able to endure higher levels of stress, particularly on smaller diameters.
Compared to normal Mild Steel, bright Mild Steel provides tighter sectional tolerances, increased straightness, and a much cleaner surface. The main advantage of cold drawn Steel is that Steel can be brought closer to the finished machine size, providing reduce machining costs. Another benefit of bright Steel bars is a marked increase in physical strength over hot rolled bars of the same section.
EN3B bright Mild Steel (070m20) used to be the most popular specification of bright Mild Steel available. It has since been replaced by steels that have a tighter chemical analysis.
EN3B Bright Mild Steel is now a general purpose Steel that is suitable for welding, can be case-hardened and is good for general machining. EN3B is generally used in engineering applications that will not be heavily stressed.
EN3B, also known as 070m20, is available from stock in rounds, flats, squares and hexagons. EN3B is a mild steel suitable for general engineering use and offers good machining and welding characteristics. Used in low stress engineering applications, can be case hardened. AISI 1020
• Material available ex stock, delivered nationwide next day.
• En3B mild steel can be cut, drilled or fabricated to your requirements.
EN3B grade round bars
EN3B is the standard for bright mild steel across the UK. It offers good machinability and weldability, making EN3B bright mild steel round bars are perfect for low-stress engineering applications and general machining. Granting accuracy and straightness in shape, they are ideal for projects that require well-defined edges and a clean surface finish.
Please note that bright mild steel round bars should not be used in applications where heavy stresses are involved. This type of round bar is particularly suitable for lightly stressed components – such as machinery parts, rollers, shafts and axles.
Bright mild steel properties
Looking at bright mild steel more generally, it’s a cold-rolled metal with greater control over dimensions and shape. Alongside a cleaner finish, this black mild steel can withstand higher pressure and tension compared to standard mild steel, though EN3B mild steel is suitable for applications that will not be heavily stressed.
Bright mild steel has better straightness for automatic bar-feeding, plus low carbon content and good malleability so it’s suitable for recycling and reworking.