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SAE J404 4145 vs AISI 4140

Strong Match — 89.7% match based on chemical composition and mechanical property overlap.

SAE J404 4145 (SAE J404:2009) and AISI 4140 are both steel grades. Both fall under the Alloy Steel category. SAE J404 4145 is typically used for chemistry-only alloy steel grade; see the composition notes for product scope, while AISI 4140 is commonly used for gears, shafts, dies, bolts, crankshafts, tooling. SAE J404 4145 is defined under SAE International, originating from United States, while AISI 4140 is defined under AISI, originating from United States.

As per chemical composition, SAE J404 4145 vs AISI 4140 is a 89.7% match. Mechanical property data is not available for both grades, so this factor could not be scored. Combined, this makes them a strong match overall at 89.7%.

Frequently Compared With SAE J404 4145:
NF A35-565 100C6 UNI 11234 100Cr6 IS 1570 (Part 4) 103Cr6 IS 1570 (Part 4) 105Cr5 IS 11169 (Part 1) 10Ni5Cr4 IS 1570 (Part 4) 10Cr20Mo6 IS 4367 10Cr9Mo10 IS 1570 (Part 4) 103Cr4 IS 11169 (Part 1) 12Cr4Mo2 IS 1570 (Part 7) 10Mo6H IS 4367 07Cr4Mo6 IS 1570 (Part 4) 07Cr4Mo6
Match Breakdown
CHEMISTRY MATCH
89.7%
MECHANICAL MATCH
No shared data
OVERALL
89.7%
Specifications
Property SAE J404 4145 AISI 4140
Standard SAE J404:2009 AISI
Category Alloy Steel Alloy Steel
C (%) 0.43-0.48 0.38–0.43
Cr (%) 0.80-1.10 0.80–1.10
Mn (%) 0.75-1.00 0.75–1.00
Mo (%) 0.15-0.25 0.15–0.25
P (%) <=0.030 ≤0.035
S (%) <=0.040 ≤0.040
Si (%) 0.15-0.35 0.15–0.35
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property SAE J404 4145 AISI 4140
Condition Not specified Quenched & Tempered
Tensile Strength Not specified 850–1000 MPa
Yield Strength Not specified ≥680 MPa
Elongation Not specified ≥13%
Hardness Not specified 248–302 HB
Impact (Charpy) Not specified ≥54 J
Typical Applications
SAE J404 4145
Chemistry-only alloy steel grade; see the composition notes for product scope
AISI 4140
Gears, shafts, dies, bolts, crankshafts, tooling
Can SAE J404 4145 Be Substituted With AISI 4140?
SAE J404 4145 and AISI 4140 overlap closely enough on chemistry and mechanical properties that AISI 4140 is often considered as a substitute for SAE J404 4145 in many applications. Always confirm the specific property range your application needs before substituting, and check with your supplier's mill certificate.
Forms & Sizes Available on M-EX
SAE J404 4145
No active listings currently.
AISI 4140
Round Bar → (3 listings)
Diameter: 50–50 mm (1.97–1.97 in)
Length: 5800–7000 mm (228.35–275.59 in)
On M-EX Right Now
SAE J404 4145
0 active listings and RFQs →
AISI 4140
3 active listings and RFQs →
Frequently Asked Questions
What is the difference between SAE J404 4145 and AISI 4140?
Both grades share a similar composition profile; see the specification table above for the exact chemistry and mechanical property values.
Can SAE J404 4145 be substituted with AISI 4140?
SAE J404 4145 and AISI 4140 overlap closely enough on chemistry and mechanical properties that AISI 4140 is often considered as a substitute for SAE J404 4145 in many applications. Always confirm the specific property range your application needs before substituting, and check with your supplier's mill certificate.