Strong Match — 86.1% match
based on chemical composition and mechanical property overlap.
BS 970 EN18D (BS 970:1955) and SAE J404 5140 (SAE J404:2009) are both steel grades.
Both fall under the Alloy Steel category.
BS 970 EN18D is defined under British Standards (BS), originating from United Kingdom, while SAE J404 5140 is defined under SAE International, originating from United States.
As per chemical composition, BS 970 EN18D vs SAE J404 5140 is a 86.1% 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 86.1%.
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property
BS 970 EN18D
SAE J404 5140
Tensile Strength
≥695 MPa (45 tons/sq in, converted)
Not specified
Yield Strength
≥525 MPa (34 tons/sq in, converted)
Not specified
Elongation
≥22%
Not specified
Hardness
201-255 HB
Not specified
Condition
Hardened and tempered R, ruling section 4 in (lowest-strength condition of the standard)
Not specified
Typical Applications
BS 970 EN18D
Not documented
SAE J404 5140
Used for gears, shafts, spindles, automotive parts, bolts, and machine components.
Can BS 970 EN18D Be Substituted With SAE J404 5140?
BS 970 EN18D and SAE J404 5140 overlap closely enough on chemistry and mechanical properties that SAE J404 5140 is often considered as a substitute for BS 970 EN18D 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 BS 970 EN18D and SAE J404 5140?
Both grades share a similar composition profile; see the specification table above for the exact chemistry and mechanical property values.
Can BS 970 EN18D be substituted with SAE J404 5140?
BS 970 EN18D and SAE J404 5140 overlap closely enough on chemistry and mechanical properties that SAE J404 5140 is often considered as a substitute for BS 970 EN18D in many applications. Always confirm the specific property range your application needs before substituting, and check with your supplier's mill certificate.