Continuously hot-dip coated strip and sheet of structural steels

Steel grades and mechanical properties (longitudinal test pieces)

Table 1

Designation Chemical composition
% by mass
max.
Mechanical properties

Steel Grade

Symbols for the types
of hot-dip coating

C Si Mn P S 0.2 %-proof
strength
Rp0,2a
MPa *
min.
Tensile
strength
Rmb
MPa *
min.
Elongation

A80c
%
min.
Steel name

Steel number

S220GD 1.0241 +Z,+ZF,+ZA,+AZ 0.20 0.60 1.70 0.10 0.045 220 300 20
S250GD 1.0242 +Z,+ZF,+ZA,+AZ,+AS 250 330 19
S280GD 1.0244 +Z,+ZF,+ZA,+AZ,+AS 280 360 18
S320GD 1.0250 +Z,+ZF,+ZA,+AZ,+AS 320 390 17
S350GD 1.0529 +Z,+ZF,+ZA,+AZ,+AS 350 420 16
S550GD 1.0531 +Z,+ZF,+ZA,+AZ 550 560 -

* 1MPa = 1 N/mm2.
a If the yield point is pronounced, the values apply to the upper yield point (ReH).
b For all grades except S550GD, a range of 140 MPa can be expected for tensile strength.
c For product thicknesses ≤ 0,70 mm (including coating) the minimum elongation values (A80) shall be reduced by 2 units.

Permissible deviations of the product analysis from specified limits on cast analysis given in Table 1

Element Specified limit of the cast analysis in Table 1
% by mass
Permissible deviation of the product analysis
% by mass
C 0.20 + 0.02
Si 0.60 + 0.03
Mn 1.70 + 0.10
P 0.10 + 0.01
S 0.045 + 0.005

coating materials

Coating
designation
Minimum coating mass, g/m2,
total both surfaces
Theoretical guidance values for
coating thickness per surface in
the single spot test μm
Density
g/cm3
Triple spot test Single spot test Typical valueb Rangec  
Zinc coating masses (Z)
Z100 100 85 7 5 to 12 7.1
Z140 140 120 10 7 to 15
Z200 200 170 14 10 to 20
Z225 225 195 16 11 to 22
Z275 275 235 20 15 to 27
Z350 350 300 25 19 to 33
Z450 450 385 32 24 to 42
Z600 600 510 42 32 to 55
Zinc-iron coating masses (ZF)
         
ZF100 100 85 7 5 to 12 7.1
ZF140 140 120 10 7 to 15
Zinc-aluminium alloy coating masses (ZA)
ZA095 95 80 7 5 to 12 6.9
ZA130 130 110 10 7 to 15
ZA185 185 155 14 10 to 20
ZA200 200 170 15 11 to 21
ZA255 255 215 20 15 to 27
ZA300 300 255 23 17 to 31
Aluminium-zinc alloy coating masses (AZ)
AZ100 100 85 13 9 to 19 3.8
AZ150 150 130 20 15 to 27
AZ185 185 160 25 19 to 33
Aluminium-silicon alloy coating masses (AS)
AS060 60 45 8 6 to 13 3.0
AS080 80 60 14 10 to 20
AS100 100 75 17 12 to 23
AS120 120 90 20 15 to 27
AS150 150 115 25 19 to 33

b Coating thicknesses can be calculated from the coating masses (see 7.8.1).
c The user can expect, that these limiting values are obtained on the upper surface and on the
reverse surface.

Surface treatment (surface protection)

Hot-dip coated flat products receive one of the following surface treatments at the producer's plant (see 7.6.2 to

The period of protection afforded is limited and depends on the atmospheric and storage conditions.
Hot-dip coated flat products are only supplied without surface treatment (untreated (U)) if expressively desired by
the purchaser on his own responsibility. In this case, there is increased risk of formation of corrosion products on
the surface during storage and transportation.