Types of Metal

Structural Steel

SANS 50025 / EN 10025 refers to the South African Standard for Structural Steel, published in 2009. EN 10025 is the European National Standard for Structural Steel developed by the European Committee for Iron and Steel Standardisation, which was used to replace the SANS 1431 standard in South Africa in 2008. The different steel grades which falls under the SANS 50025 / EN 10025 standard refers to the minimum yield strength of the specific grade, for example S355 refers to Structural Steel with a minimum yield strength of 355MPa.

The structural steel grades can also have the following symboks as suffixes, each symbol referring to a property the material contains:

General
  • S - Structural Steel
  • E - Engineering Steel
  • Number (for example: S235) - Minimum yield strength in MPa at 16mm
Longitudinal Charpy V-notch:
  • JR - Impacts 27 J at +20°C
  • J0 - Impacts 27 J at 0°C
  • J2 - Impacts 27 J at -20°C
  • K2 - Impacts 40 J at -20°C
  • N - Impacts temp not lower than -20°C
  • NL - Impacts temp not lower than -50°C
  • M - Impacts temp not lower than -20°C
  • ML - Impacts temp not lower than -50°C
  • Q - Impacts temp not lower than -20°C
  • QL - Impacts temp not lower than -40°C
  • QL1 - Impacts temp not lower than -60°C
Supply in:
  • +AR - As rolled conditions
  • +N - Normalized/normalized rolled conditions
C - Grade suitable for cold forming
Z - Grade with improved properties perpendicular to the surface
W - Improved atmospheric corrosion resistance
P - Greater phosphorus content (Grade 355 only)

Chemical Composition

Grade Maximum carbon content for nominal product thickness t ≤ 16 Mn max Si max P max S max Cu max N max
S235 JR +N 0.17 1.40 - 0.035 0.035 0.55 0.012
S235 JR +AR 0.17 1.40 - 0.035 0.035 0.55 0.012
S235 J0 +N 0.17 1.40 - 0.030 0.030 0.55 0.012
S235 J0 +AR 0.17 1.40 - 0.030 0.030 0.55 0.012
S235 J2 +N 0.17 - - 0.025 0.025 0.55 -
S275 JR +N 0.21 1.50 - 0.035 0.035 0.55 0.012
S275 JR +AR 0.21 1.50 - 0.035 0.035 0.55 0.012
S275 J0 +N 0.18 1.50 - 0.030 0.030 0.55 0.012
S275 J0 +AR 0.18 1.50 - 0.030 0.030 0.55 0.012
S275 J2 +N 0.18 - - 0.025 0.025 0.55 -
S355 JR +N 0.24 1.60 0.55 0.035 0.035 0.55 0.012
S355 JR +AR 0.24 1.60 0.55 0.035 0.035 0.55 0.012
S355 J0 +N 0.20 1.60 0.55 0.030 0.030 0.55 0.012
S355 J0 +AR 0.20 1.60 0.55 0.030 0.030 0.55 0.012
S355 J2 +N 0.20 1.60 0.55 0.025 0.025 0.55 -

Mechanical Properties:

Grade Yield (Reh) min Tensile (Rm) Elongation (%) Charpy V-notch longitudinal
Strength at t = 16mm (MPa) 1.5 < t ≤ 2 2 < t ≤ 2.5 2.5< t ≤ 3 3 < t ≤ 40 Temp p (°C) Energy (J) t = 16mm
S235JR 235 360/510 17 18 19 24 20 27
S235J0 235 360/510 17 18 19 24 0 27
S235J2 235 360/510 17 18 19 24 -20 27
S275JR 275 410/560 15 16 17 21 20 27
S275J0 275 410/560 15 16 17 21 0 27
S275J2 275 410/560 15 16 17 21 -20 27
S355JR 355 470/630 14 15 16 20 20 27
S355J0 355 470/630 14 15 16 20 0 27
S355J2 355 470/630 14 15 16 20 -20 27
S355K2 355 470/630 14 15 16 20 -20 40

The structural steel's strength-to-weight ratio is high which makes it the preferred material for skyscraper buildings. The required material to carry the load is not as much as with other materials. Steel has the advantage of high strength, toughness, fire resistance and good constructibility. In the construction industry, structural steel is the most commonly used type of steel.