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
0.67-0.75
0.17-0.37
0.90-1.20
<=0.035
<=0.035
<=0.25
<=0.30
<=0.25
Mechanical Properties
Tensile Strength
>=785 MPa
Yield Strength
>=450 MPa
Elongation
>=8%
Hardness
<=285 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
785 MPa
Lower yield strength ReL, min
450 MPa
Elongation after fracture A, min
8 %
Reduction of area Z, min
30 %
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.
Source: GB/T 699:2015, Table 2
Maximum delivery hardness2 delivery states
Delivery state
Maximum hardness (HBW)
Not heat treated
285
Annealed
229
Source: GB/T 699:2015, Table 2
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