Minimal Match — 35% match
based on chemical composition and mechanical property overlap.
BS 970 (Part 1) 708M40 (BS 970 (Part 1):1991) and GB/T 3077 12Cr2Ni4A (GB/T 3077-2015) are both steel grades.
Both fall under the Alloy Steel category.
BS 970 (Part 1) 708M40 is typically used for used for axles, gears, shafts, studs, crankshafts, and heavy-duty machinery parts., while GB/T 3077 12Cr2Ni4A is commonly used for used for gears, shafts, pinions, aircraft parts, heavy-duty bearings, and transmission components..
BS 970 (Part 1) 708M40 is defined under British Standards (BS), originating from United Kingdom, while GB/T 3077 12Cr2Ni4A is defined under Guobiao Standards (GB/T), originating from China.
As per chemical composition, BS 970 (Part 1) 708M40 vs GB/T 3077 12Cr2Ni4A is a 51.4% match.
Mechanical property data is not available for both grades, so this factor could not be scored.
Combined, this makes them a minimal match overall at 35%.
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) 708M40
GB/T 3077 12Cr2Ni4A
Tensile Strength
Not specified
980-1180 MPa
Yield Strength
Not specified
785-980 MPa
Elongation
Not specified
10-14%
Hardness
Not specified
58-62 HRC (case)
Typical Applications
BS 970 (Part 1) 708M40
Used for axles, gears, shafts, studs, crankshafts, and heavy-duty machinery parts.
GB/T 3077 12Cr2Ni4A
Used for gears, shafts, pinions, aircraft parts, heavy-duty bearings, and transmission components.
Key Differences
BS 970 (Part 1) 708M40 specifies Mo which is not specified for GB/T 3077 12Cr2Ni4A.
GB/T 3077 12Cr2Ni4A specifies Si, Ni, P, S which are not specified for BS 970 (Part 1) 708M40.
Can BS 970 (Part 1) 708M40 Be Substituted With GB/T 3077 12Cr2Ni4A?
BS 970 (Part 1) 708M40 and GB/T 3077 12Cr2Ni4A share some compositional similarity but differ enough that substitution should not be assumed. Review the differences above carefully, and consult the applicable standard or a metallurgist before using one in place of the other.
What is the difference between BS 970 (Part 1) 708M40 and GB/T 3077 12Cr2Ni4A?
BS 970 (Part 1) 708M40 specifies Mo which is not specified for GB/T 3077 12Cr2Ni4A. GB/T 3077 12Cr2Ni4A specifies Si, Ni, P, S which are not specified for BS 970 (Part 1) 708M40.
Can BS 970 (Part 1) 708M40 be substituted with GB/T 3077 12Cr2Ni4A?
BS 970 (Part 1) 708M40 and GB/T 3077 12Cr2Ni4A share some compositional similarity but differ enough that substitution should not be assumed. Review the differences above carefully, and consult the applicable standard or a metallurgist before using one in place of the other.