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
Cr
Ni
Cu
0.52-0.60
0.17-0.37
0.50-0.80
<=0.035
<=0.035
<=0.25
<=0.30
<=0.25
Mechanical Properties
Tensile Strength
>=645 MPa
Yield Strength
>=380 MPa
Elongation
>=13%
Hardness
<=255 HB (as delivered, not heat treated)
Condition
Normalized 25 mm sample blank, bars up to 80 mm; hardness for delivery state
More data from GB/T 699:2015
From the standard
Mechanical properties (normalized)for bars up to 80 mm
Tensile strength Rm, min
645 MPa
Lower yield strength ReL, min
380 MPa
Elongation after fracture A, min
13 %
Reduction of area Z, min
35 %
Longitudinal tensile properties from the sample blank; for 80 to 250 mm bars elongation may be 2 percent (absolute) and reduction of area 5 percent (absolute) lower. Yield may be replaced by Rp0.2 where there is no distinct yield.
Permissible adjustment: +/-30 deg C normalizing, +/-20 deg C quenching, +/-50 deg C tempering; hold at least 30 min (1 h for 600 deg C tempering); quench in oil for 75, 80 and 85 steels, otherwise water.