IS 1570 (Part 4):1988 20C15 Steel: Specifications & Listings
IS 1570 (Part 4):1988 20C15: 20C15: alloy steel (constructional or spring group) with specified chemical composition. Specified in IS 1570 (Part 4):1988.
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
0.16-0.24
0.10-0.35
1.30-1.70
Mechanical Properties
Tensile Strength
690-840 MPa
Yield Strength
>=450 MPa (0.2 % proof stress)
Elongation
>=16%
Izod Impact
>=48 J
Hardness
201-248 HBS (guidance only)
Condition
Bars and forgings, hardened and tempered (oil hardened unless stated), limiting ruling section 30 mm
More data from IS 1570 (Part 4):1988
From the standard
Tensile limits, hot rolled or normalized5 ruling sections
Limiting ruling section (mm)
Tensile strength (MPa)
0.2 % proof stress, min, if specified (MPa)
Elongation, min (%)
15
540-640
350
20
30
540-640
320
20
63
510-610
310
20
100
510-610
290
20
over 100 to 150
490-590
280
20
Plates, sections, bars, billets and forgings in the hot rolled or normalized condition.
Source: IS 1570 (Part 4):1988, Table 2
Properties, hardened and tempered2 strength levels
Limiting ruling section (mm)
Tensile strength (MPa)
0.2 % proof stress, min (MPa)
Elongation, min (%)
Izod impact, min (J)
Brinell hardness (HBS)
63
590-740
390
18
48
170-217
30
690-840
450
16
48
201-248
Bars and forgings, oil hardened unless stated; hardness is for guidance only.