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
0.26-0.34
0.10-0.40
0.60-1.00
<=0.05
<=0.05
More data from BS 970 (Part 3):1991
From the standard
Other composition limits
Steel group
Carbon and carbon manganese steel (Table 13)
Condition of supply
Bright bars: cold drawn, turned or precision ground, in straight lengths
Maximum unless a range is stated.
Source: BS 970 (Part 3):1991, Table 13
Mechanical properties by heat treatment condition
Condition
Reference symbol
Size (mm)
Tensile strength Rm (MPa)
Yield Re, min (MPa)
Elongation, min (%)
Impact Izod, min (J)
Impact KCV, min (J)
Rp0.2, min (MPa)
Hardness HB
Notes
Normalized + turned or ground
≥ 6 ≤ 150
490 min.
245
20
—
—
—
143-192
Normalized + turned or ground
> 150 ≤ 250
460 min.
230
19
—
—
—
134-183
Hot rolled + cold drawn or hot rolled + cold drawn + ground
≥ 6 ≤ 13
620 min.
480
9
—
—
460
Hot rolled + cold drawn or hot rolled + cold drawn + ground
> 13 ≤ 16
600 min.
470
10
—
—
450
Hot rolled + cold drawn or hot rolled + cold drawn + ground
> 16 ≤ 40
570 min.
430
11
—
—
400
Hot rolled + cold drawn or hot rolled + cold drawn + ground
> 40 ≤ 63
560 min.
415
12
—
—
345
Hot rolled + cold drawn or hot rolled + cold drawn + ground
> 63 ≤ 76
530 min.
385
12
—
—
320
Hardened and tempered + turned or ground
P
≥ 6 ≤ 63
550-700
340
18
34
28
310
152-207
Hardened and tempered + turned or ground
Q
≥ 6 ≤ 19
625-775
415
16
34
28
400
179-229
Hardened and tempered + cold drawn or hardened and tempered + cold drawn + ground
P
≥ 6 ≤ 63
550-700
385
13
34
—
340
152-207
Hardened and tempered + cold drawn or hardened and tempered + cold drawn + ground
Q
≥ 6 ≤ 19
625-775
460
12
34
—
430
179-229
Condition letters P to Z are the tensile strength ranges of Table 29. Rp0.2 applies when specifically ordered (note 3). Hardness HB is for guidance only except in the softened condition (note 13). Impact: Izod, or KCV when the standard impact test is not required (option A.3).
Source: BS 970 (Part 3):1991, Table 20
Heat treatment temperatures
Normalizing temperature
860-890 deg C
Hardening temperature
860-890 deg C, oil or water
Tempering temperature
550-660 deg C
Normalizing, hardening and tempering temperatures as given in Tables 27 and 28 (clause 4.2); Table 22 hardening temperatures for case hardening steels.
Source: BS 970 (Part 3):1991, Table 27 and Table 28