Close Alternative — 83.4% match
based on chemical composition and mechanical property overlap.
GB/T 3077 42CrMo (GB/T 3077:2015) and BS 970 (Part 1) 708M40 (BS 970 (Part 1):1983) are both steel grades.
Both fall under the Alloy Steel category.
GB/T 3077 42CrMo is typically used for gears, heavy shafts, axles, bolts, pressure vessels, forgings, while BS 970 (Part 1) 708M40 is commonly used for through hardening steel for mechanical and allied engineering purposes; supplied in the hardened and tempered conditions of table 6..
GB/T 3077 42CrMo is defined under Guobiao Standards (GB/T), originating from China, while BS 970 (Part 1) 708M40 is defined under British Standards (BS), originating from United Kingdom.
As per chemical composition, GB/T 3077 42CrMo vs BS 970 (Part 1) 708M40 is a 83.4% 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 83.4%.
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property
GB/T 3077 42CrMo
BS 970 (Part 1) 708M40
Tensile Strength
>=1080 MPa
Not specified
Yield Strength
>=930 MPa
Not specified
Elongation
>=12%
Not specified
Hardness
<=229 HB
Not specified
Condition
Quenched and tempered, test sample 25 mm; hardness is for bars delivered annealed or high temperature tempered
Not specified
Typical Applications
GB/T 3077 42CrMo
gears, heavy shafts, axles, bolts, pressure vessels, forgings
BS 970 (Part 1) 708M40
Through hardening steel for mechanical and allied engineering purposes; supplied in the hardened and tempered conditions of Table 6.
Key Differences
GB/T 3077 42CrMo specifies Si, Cu which are not specified for BS 970 (Part 1) 708M40.
Can GB/T 3077 42CrMo Be Substituted With BS 970 (Part 1) 708M40?
GB/T 3077 42CrMo and BS 970 (Part 1) 708M40 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 GB/T 3077 42CrMo and BS 970 (Part 1) 708M40?
GB/T 3077 42CrMo specifies Si, Cu which are not specified for BS 970 (Part 1) 708M40.
Can GB/T 3077 42CrMo be substituted with BS 970 (Part 1) 708M40?
GB/T 3077 42CrMo and BS 970 (Part 1) 708M40 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.