Close Alternative — 84% match
based on chemical composition and mechanical property overlap.
GB/T 3077 42CrMo (GB/T 3077:2015) and SAE J404 4140 (SAE J404:2000) 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 SAE J404 4140 is commonly used for chemistry-only alloy steel grade; see the composition notes for product scope.
GB/T 3077 42CrMo is defined under Guobiao Standards (GB/T), originating from China, while SAE J404 4140 is defined under SAE International, originating from United States.
As per chemical composition, GB/T 3077 42CrMo vs SAE J404 4140 is a 84% 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 84%.
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
SAE J404 4140
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
SAE J404 4140
Chemistry-only alloy steel grade; see the composition notes for product scope
Key Differences
GB/T 3077 42CrMo specifies Cu which is not specified for SAE J404 4140.
Can GB/T 3077 42CrMo Be Substituted With SAE J404 4140?
GB/T 3077 42CrMo and SAE J404 4140 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 SAE J404 4140?
GB/T 3077 42CrMo specifies Cu which is not specified for SAE J404 4140.
Can GB/T 3077 42CrMo be substituted with SAE J404 4140?
GB/T 3077 42CrMo and SAE J404 4140 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.