BS 970 (Part 1) 817A42 vs IS 1570 (Part 4) 40Ni6Cr4Mo3
Close Alternative — 82.5% match
based on chemical composition and mechanical property overlap.
BS 970 (Part 1) 817A42 (BS 970 (Part 1):1983) and IS 1570 (Part 4) 40Ni6Cr4Mo3 (IS 1570 (Part 4):1988) are both steel grades.
Both fall under the Alloy Steel category.
BS 970 (Part 1) 817A42 is defined under British Standards (BS), originating from United Kingdom, while IS 1570 (Part 4) 40Ni6Cr4Mo3 is defined under Bureau of Indian Standards (IS), originating from India.
As per chemical composition, BS 970 (Part 1) 817A42 vs IS 1570 (Part 4) 40Ni6Cr4Mo3 is a 82.5% match.
Mechanical property data is not available for both grades, so this factor could not be scored.
Combined, this makes them a close alternative overall at 82.5%.
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property
BS 970 (Part 1) 817A42
IS 1570 (Part 4) 40Ni6Cr4Mo3
Tensile Strength
Not specified
1190-1340 MPa
Yield Strength
Not specified
>=930 MPa (0.2 % proof stress)
Elongation
Not specified
>=10%
Izod Impact
Not specified
>=30 J
Hardness
Not specified
341-401 HBS (guidance only)
Condition
Not specified
Bars and forgings, hardened and tempered (oil hardened unless stated), limiting ruling section 30 mm
Typical Applications
BS 970 (Part 1) 817A42
Through hardening steel for mechanical and allied engineering purposes; supplied in the hardened and tempered conditions of Table 6.
IS 1570 (Part 4) 40Ni6Cr4Mo3
Not documented
Key Differences
BS 970 (Part 1) 817A42 specifies P, S which are not specified for IS 1570 (Part 4) 40Ni6Cr4Mo3.
IS 1570 (Part 4) 40Ni6Cr4Mo3 specifies Si which is not specified for BS 970 (Part 1) 817A42.
Can BS 970 (Part 1) 817A42 Be Substituted With IS 1570 (Part 4) 40Ni6Cr4Mo3?
BS 970 (Part 1) 817A42 and IS 1570 (Part 4) 40Ni6Cr4Mo3 are a close alternative rather than a direct substitute. Some properties overlap well, but check the specific chemistry and mechanical rows above against your application's requirements before treating them as interchangeable.
What is the difference between BS 970 (Part 1) 817A42 and IS 1570 (Part 4) 40Ni6Cr4Mo3?
BS 970 (Part 1) 817A42 specifies P, S which are not specified for IS 1570 (Part 4) 40Ni6Cr4Mo3. IS 1570 (Part 4) 40Ni6Cr4Mo3 specifies Si which is not specified for BS 970 (Part 1) 817A42.
Can BS 970 (Part 1) 817A42 be substituted with IS 1570 (Part 4) 40Ni6Cr4Mo3?
BS 970 (Part 1) 817A42 and IS 1570 (Part 4) 40Ni6Cr4Mo3 are a close alternative rather than a direct substitute. Some properties overlap well, but check the specific chemistry and mechanical rows above against your application's requirements before treating them as interchangeable.