Close Alternative — 78.6% match
based on chemical composition and mechanical property overlap.
GB/T 3077 50CrMo (GB/T 3077:2015) and BS 970 (Part 3) 708M40 (BS 970 (Part 3):1991) are both steel grades.
Both fall under the Alloy Steel category.
GB/T 3077 50CrMo is typically used for hot-rolled or forged structural alloy steel bars, while BS 970 (Part 3) 708M40 is commonly used for bright cold finished bars (cold drawn, turned or precision ground) for general engineering purposes, in straight lengths; alloy direct hardening steel (table 16).
GB/T 3077 50CrMo is defined under Guobiao Standards (GB/T), originating from China, while BS 970 (Part 3) 708M40 is defined under British Standards (BS), originating from United Kingdom.
As per chemical composition, GB/T 3077 50CrMo vs BS 970 (Part 3) 708M40 is a 78.6% 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 78.6%.
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 50CrMo
BS 970 (Part 3) 708M40
Tensile Strength
>=1130 MPa
Not specified
Yield Strength
>=930 MPa
Not specified
Elongation
>=11%
Not specified
Hardness
<=248 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 50CrMo
Hot-rolled or forged structural alloy steel bars
BS 970 (Part 3) 708M40
Bright cold finished bars (cold drawn, turned or precision ground) for general engineering purposes, in straight lengths; alloy direct hardening steel (Table 16)
Key Differences
GB/T 3077 50CrMo specifies Cu which is not specified for BS 970 (Part 3) 708M40.
Can GB/T 3077 50CrMo Be Substituted With BS 970 (Part 3) 708M40?
GB/T 3077 50CrMo and BS 970 (Part 3) 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 50CrMo and BS 970 (Part 3) 708M40?
GB/T 3077 50CrMo specifies Cu which is not specified for BS 970 (Part 3) 708M40.
Can GB/T 3077 50CrMo be substituted with BS 970 (Part 3) 708M40?
GB/T 3077 50CrMo and BS 970 (Part 3) 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.