Close Alternative — 85% match
based on chemical composition and mechanical property overlap.
JIS G4104 SCr420 (JIS G 4104:1979) and SAE J404 5120 (SAE J404:2009) are both steel grades.
Both fall under the Alloy Steel category.
JIS G4104 SCr420 is typically used for case hardened gears, shafts, cams, while SAE J404 5120 is commonly used for case hardened gears, pins, shafts, cams, automotive transmission parts.
JIS G4104 SCr420 is defined under Japanese Industrial Standards (JIS), originating from Japan, while SAE J404 5120 is defined under SAE International, originating from United States.
As per chemical composition, JIS G4104 SCr420 vs SAE J404 5120 is a 85% 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 85%.
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property
JIS G4104 SCr420
SAE J404 5120
Tensile Strength
≥830 MPa
Not specified
Case Hardness HRC
58–62
Not specified
Core Hardness HB
235–293
Not specified
Typical Applications
JIS G4104 SCr420
Case hardened gears, shafts, cams
SAE J404 5120
Case hardened gears, pins, shafts, cams, automotive transmission parts
Can JIS G4104 SCr420 Be Substituted With SAE J404 5120?
JIS G4104 SCr420 and SAE J404 5120 overlap closely enough on chemistry and mechanical properties that SAE J404 5120 is often considered as a substitute for JIS G4104 SCr420 in many applications. Always confirm the specific property range your application needs before substituting, and check with your supplier's mill certificate.
What is the difference between JIS G4104 SCr420 and SAE J404 5120?
Both grades share a similar composition profile; see the specification table above for the exact chemistry and mechanical property values.
Can JIS G4104 SCr420 be substituted with SAE J404 5120?
JIS G4104 SCr420 and SAE J404 5120 overlap closely enough on chemistry and mechanical properties that SAE J404 5120 is often considered as a substitute for JIS G4104 SCr420 in many applications. Always confirm the specific property range your application needs before substituting, and check with your supplier's mill certificate.