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
<=0.20
<=0.55
<=1.70
<=0.035
<=0.035
<=0.05
<=0.13
<=0.05
<=0.30
<=0.80
<=0.40
<=0.20
<=0.015
Mechanical Properties
Tensile Strength
520-680 MPa
Yield Strength
>=420 MPa
Elongation
>=20%
Condition
Hot-rolled (as-rolled), nominal thickness or diameter up to 16 mm for yield; tensile strength for up to 100 mm; elongation longitudinal, up to 40 mm
More data from GB/T 1591:2018
From the standard
Upper yield strength by thickness9 thickness ranges
Thickness or diameter (mm)
Upper yield strength ReH, min (MPa)
up to 16
420
over 16 to 40
410
over 40 to 63
390
over 63 to 80
370
over 80 to 100
370
over 100 to 150
350
over 150 to 200
-
over 200 to 250
-
over 250 to 400
-
Hot-rolled (as-rolled) condition.
Source: GB/T 1591:2018, Table 7
Tensile strength by thickness4 thickness ranges
Thickness or diameter (mm)
Tensile strength Rm (MPa)
up to 100
520-680
over 100 to 150
500-650
over 150 to 250
-
over 250 to 400
-
Hot-rolled (as-rolled) condition.
Source: GB/T 1591:2018, Table 7
Elongation after fracture by thickness4 thickness ranges
Thickness or diameter (mm)
Longitudinal A, min (%)
up to 40
20
over 40 to 63
19
over 63 to 100
19
over 100 to 150
19
Hot-rolled (as-rolled) condition.
Source: GB/T 1591:2018, Table 8
Charpy V-notch impact energy1 test temperature(s)
Test temperature
Longitudinal KV2, min (J)
Transverse KV2, min (J)
20 deg C
34
27
Standard 10 mm x 10 mm x 55 mm specimen.
Source: GB/T 1591:2018, Table 11
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