Close Alternative — 80.2% match
based on chemical composition and mechanical property overlap.
GB/T 3077 20CrMn (GB/T 3077:2015) and SAE J404 5120 (SAE J404:2009) are both steel grades.
Both fall under the Alloy Steel category.
GB/T 3077 20CrMn is typically used for hot-rolled or forged structural alloy steel bars, while SAE J404 5120 is commonly used for case hardened gears, pins, shafts, cams, automotive transmission parts.
GB/T 3077 20CrMn is defined under Guobiao Standards (GB/T), originating from China, while SAE J404 5120 is defined under SAE International, originating from United States.
As per chemical composition, GB/T 3077 20CrMn vs SAE J404 5120 is a 80.2% 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 80.2%.
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 20CrMn
SAE J404 5120
Tensile Strength
>=930 MPa
Not specified
Yield Strength
>=735 MPa
Not specified
Elongation
>=10%
Not specified
Hardness
<=187 HB
Not specified
Condition
Quenched and tempered, test sample 15 mm; hardness is for bars delivered annealed or high temperature tempered
Not specified
Typical Applications
GB/T 3077 20CrMn
Hot-rolled or forged structural alloy steel bars
SAE J404 5120
Case hardened gears, pins, shafts, cams, automotive transmission parts
Key Differences
GB/T 3077 20CrMn specifies Cu which is not specified for SAE J404 5120.
Can GB/T 3077 20CrMn Be Substituted With SAE J404 5120?
GB/T 3077 20CrMn and SAE J404 5120 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 20CrMn and SAE J404 5120?
GB/T 3077 20CrMn specifies Cu which is not specified for SAE J404 5120.
Can GB/T 3077 20CrMn be substituted with SAE J404 5120?
GB/T 3077 20CrMn and SAE J404 5120 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.