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
Mo
Ni
<=0.12
<=1.0
<=2.0
<=0.060
0.15-0.35
17.0-19.0
<=1.00
8.0-10.0
Mechanical Properties
Condition
Softened, 1000-1100 deg C
Tensile Strength
510 MPa min
Yield Strength
190 MPa min (0.2% proof)
Elongation
40 % min
Hardness
183 HB max
More data from BS 970 (Part 1):1991
From the standard
Other composition limits
Category
Category 1 steel (note 7)
Molybdenum
1.00 % maximum, optional addition (note 37)
Maximum unless a range is stated.
Source: BS 970 (Part 1):1991, Table 11
Properties in the softened condition
Softening temperature
1000-1100 deg C
Maximum section
160 mm
Tensile strength, min
510 MPa
Elongation, min
40 %
Rp0.2, min (when specified)
190 MPa
Rp1.0, min (when specified)
225 MPa
Hardness, max
183 HB
Straightening by reeling or cold rectification can increase the surface hardness above the specified maximum (note 36). 1 N/mm2 = 1 MPa.
Source: BS 970 (Part 1):1991, Table 11
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