Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Chemical Composition (%)
C
Si
Mn
P
S
Nb
V
Ti
Cr
Ni
Cu
Mo
N
B
Al
<=0.18
<=0.60
<=2.00
<=0.030
<=0.025
0.01-0.11
0.01-0.12
0.006-0.05
<=0.80
<=0.80
<=0.80
<=0.30
<=0.025
<=0.004
>=0.015
Mechanical Properties
Tensile Strength
670-830 MPa
Yield Strength
>=550 MPa
Elongation
>=16%
Condition
Thermomechanical processed (TMCP), nominal thickness or diameter up to 16 mm (tensile strength: up to 40 mm)
More data from GB/T 1591:2018
From the standard
Upper yield strength by thickness6 thickness ranges
Thickness or diameter (mm)
Upper yield strength ReH, min (MPa)
up to 16
550
over 16 to 40
540
over 40 to 63
530
over 63 to 80
510
over 80 to 100
500
over 100 to 120
-
Thermomechanical processed (TMCP) condition.
Source: GB/T 1591:2018, Table 10
Tensile strength by thickness5 thickness ranges
Thickness or diameter (mm)
Tensile strength Rm (MPa)
up to 40
670-830
over 40 to 63
620-810
over 63 to 80
600-790
over 80 to 100
590-780
over 100 to 120
-
Thermomechanical processed (TMCP) condition.
Source: GB/T 1591:2018, Table 10
Elongation after fracturesingle value
Elongation A, min
16 %
Single value printed for all thicknesses.
Source: GB/T 1591:2018, Table 10
Charpy V-notch impact energy1 test temperature(s)
Test temperature
Longitudinal KV2, min (J)
Transverse KV2, min (J)
-20 deg C
47
27
Standard 10 mm x 10 mm x 55 mm specimen.
Source: GB/T 1591:2018, Table 11
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