S355J5W fine grained atmospheric corrosion resistant weathering
structural steel plate
S355J5W+M STRUCTURAL STEEL is a structural steel with improved
atmospheric corrosion resistance. Due to its chemical composition,
this material develops a patina with increased resistance against
the atmospheric corrosion in comparison with the normal structural
steels. The improved atmospheric corrosion resistance property is
defined by fulfilling the weather resistance I-index in accordance
with ASTM G101.
S355J5W+M STRUCTURAL STEEL has minimum yield strength of 355 MPa in
its delivery condition ex works (referring to the lowest thickness
range). The thermomechanical rolling process allows using less
alloying elements, leading to a lower carbon equivalent and hence
an improved weldability compared to normalized weathering steels of
the same strength. The steel can therefore especially be used in
steel constructions for bridges and high rise buildings where
weathering steel with good weldability is demanded. Special
building authority approvals (e.g. European Technical Approval) may
have to be considered.
Product description
Designation and range of application
S355J5W+M STRUCTURAL STEEL can be delivered as follows:
· Low temperature quality with minimum impact values at -50 °C:
applicable in terms of S355J5W+M
S355J5W+M STRUCTURAL STEEL can be delivered in thickness from 8 to
120 mm.
Chemical composition
For the ladle analysis the following limiting values are applicable
in %:
| C | Si | Mn | P | S | Nb | V | Al | Ti | Cr | Ni | Mo | Cu | N |
| ≤0.08 | ≤0.45 | ≤1.40 | ≤0.020 | ≤0.002 | ≤0.05 | ≤0.01 | ≥0.02 | ≤0.015 | ≤0.40-0.60 | ≤0.50 | ≤0.08 | 0.25-0.40 | ≤0.01 |
Delivery condition
Thermomechanically rolled.
Mechanical properties in the delivery condition
Tensile test at ambient temperature – transverse test specimens
Plate thickness t [mm] | Minimum yield strength ReH [MPa] | Tensile strength Rm [MPa] | Minimum elongation A5 [%] |
| t ≤ 16 | 355 | 470-630 | 20 |
| 16 < t ≤ 40 | 345 |
| 40 < t ≤ 63 | 335 | 19 |
| 63 < t ≤ 100 | 325 | 18 |
| 100 < t ≤ 120 | 315 |
| 120 < t ≤ 150 | 295 | 450-600 | 18 |
Impact test on Charpy-V-specimens
| Material | Specimen direction | Impact energy KV2 [J] at test temperature of |
| -20 °C | -50 °C |
| S355J5W+M | longitudinal | - | 20 |
The specified minimum value is the average of 3 tests. One
individual value may be below the minimum average value specified,
provided that it is not less than 70 % of that value. Undersize
specimens are admitted for plate thickness ≤ 12 mm, the minimum
specimen width is 5 mm. The minimum impact energy will be decreased
proportionally.
Testing
Tensile test and impact tests are carried out with respect to EN
10025-5 once per heat, 40 t and thickness range as specified for
the yield strength. Tests on every mother plate are possible on
request.
The test pieces are taken and prepared according to parts 1 and 5
of EN 10025.
Identification of plates
Unless otherwise agreed, the marking is carried out via steel
stamps with at least the following information:
· steel grade (S355J5W+M)
· heat number
· number of mother plate and individual plate
· the manufacturer’s symbol
· inspection representative’s sign
Atmospheric corrosion resistance
Atmospheric corrosion resistance means that the steel - due to the
chemical composition - presents a higher resistance against
atmospheric corrosion in comparison to unalloyed steels because a
protective coating on the surface is formed influenced by the
weather, which protects the surface and decelerates the normal
corrosion process. This property is defined by the weather
resistance index I > 6.0 in accordance with ASTM G 101.
Generally, the corrosion velocity decreases with increasing service
life. Even after the formation of the patina, a total stop of the
corrosion process is not achieved. However, the patina offers - in
comparison to unalloyed steels - a better protection against
atmospheric corrosion in industrial, city or rural atmosphere,
which enables the application of uncoated steels under certain
circumstances. Initial formation, time of development and
protective effect of the patina on steels with improved atmospheric
corrosion resistance are extremely
depending on the constructional design and the atmospheric and
environmental conditions in the respective case. In any case, usual
constructional standards for the construction with steels with
improved atmospheric corrosion resistance are to be observed.
Processing
The entire processing and application techniques are of fundamental
importance to the reliability of the parts and assemblies made from
this steel. The user should ensure that his design, construction
and processing methods are with the material, correspond to the
state-of-the-art that the fabricator has to comply with and are
suitable for the intended use. The customer is responsible for the
selection of the material. The recommendations in accordance with
EN 1011-2, guideline DASt 007, SEW 088 as well as recommendations
regarding job safety in accordance with national rules should be
observed.
Cold forming
S355J5W+M STRUCTURAL STEEL can be cold formed, i.e. forming at
temperatures below 580 °C, as any comparable structural steel in
accordance with EN 10025. Cold forming is always related to a
hardening of the steel and to a decrease in toughness. This change
in the mechanical properties can in general be partially recovered
through a subsequent stress relief heat treatment. Flame cut or
sheared edges in the bending area should be ground before
cold forming. For larger cold forming degrees we recommend
consulting us prior to ordering.
Hot forming
Hot forming, i.e. forming at temperatures above 580 °C, leads to
changes in the original material condition. It is impossible to
re-establish the same material properties that had been achieved
during the original manufacture through a further treatment.
Therefore hot forming is not permitted.
Flame cutting and welding
S355J5W+M STRUCTURAL STEEL has despite its weathering property a
good weldability if the general technical rules (see EN 1011) are
respected. The fabrication by flame cutting and welding has to be
carried out similarly to normalized structural steels of EN 10025
at the same strength and dimensions. However the hardenability of
the steel is increased due to the Cu and Cr alloying. Owing to the
low carbon content oxygen cutting, plasma and laser cutting can be
carried out up to large thickness without preheating. The preheat
conditions during welding have to be adapted to the slightly
increased carbon equivalent compared to non-weathering
thermomechanically rolled steels. If necessary, the corrosion
resistance of the welding deposit has to be assured by selection of
adequate weld metals or other anti-corrosion measures.
Heat treatment
Welded joints of S355J5W+M STRUCTURAL STEEL are usually used in
welded condition. If a stress relief heat treatment is necessary,
it is carried out in the temperature range between 530 and 580 °C
with cooling in air. The holding time should not exceed 4 hours
(even if multiple operations are carried out). For particular heat
treatment requirements we recommend consulting us prior to
ordering.
General technical delivery requirements
Unless otherwise agreed, the general technical delivery
requirements in accordance with EN 10021 apply.
Tolerances
Unless otherwise agreed, tolerances are in accordance with 10029,
with class A for the thickness.
Surface quality
Unless otherwise agreed, the specifications will be in accordance
with EN 10163, class A2.
Ultrasonic testing
Unless otherwise agreed, S355J5W+M STRUCTURAL STEEL meets the
requirements of class S0E0 according to EN 10160.
General note
If special requirements, which are not covered in this material
data sheet, are to be met by the steel due to its intended use or
processing, these requirements are to be agreed before placing the
order.
Production process
