Hot rolled structural steels – Part 5:Steels with improved resistance to atmospheric corrosion for structural uses.

these products are characterised by guaranteed minimum yield, tensile, elongation and resilience limits.
They are supplied with CE marking.

This category of products is suitable for the construction of items, such as welded structural steelworks that do not require significant deformations of the individual components. As it bears the CE marking, it is suitable for use in civil structures and, with SnnnJ0 and J2 grades, even at low temperatures with unaltered guaranteed minimum resilience values ​​at 0 and -20 ° C, respectively.

In particular, the presence of elements, such as P, Cu, Cr, Ni and Mo in the chemical analysis, facilitates the formation of oxide layers on the surface that self-protect the material (self-passivation), making it suitable for use in structures exposed to adverse weather conditions ( e.g. bridge structures, external walls of buildings, etc).

In order for the self-passivation and self-protection process to be triggered, this category of product, after the production process requires exposure to natural atmospheric cycles with alternating wet and dry periods. Otherwise, where exposure to the dry-wet cycles described is not facilitated, the product starts to corrode, hence in such cases alternating dry – wet cycles must be taken into consideration before implementing the product.

The surface of the passivated product shows a characteristic and homogeneous browning.

These steels do not normally require surface protection, except for the cases of applications in particularly aggressive environments (i.e. marine environments).

The tables below show only the main characteristics of the products listed and not all the technical supply conditions. For further details, please refer to the full contents of the standards mentioned on this page.