Strong Match — 86.9% match
based on chemical composition and mechanical property overlap.
ASTM A240/A240M S40300 (ASTM A240/A240M:2025) and BS 970 (Part 3) 403S17 (BS 970 (Part 3):1991) are both steel grades.
Both fall under the Stainless Steel category.
ASTM A240/A240M S40300 is typically used for pressure vessels and general applications (plate, sheet and strip), while BS 970 (Part 3) 403S17 is commonly used for bright cold finished bars (cold drawn, turned or precision ground) for general engineering purposes, in straight lengths; ferritic stainless steel (table 17).
ASTM A240/A240M S40300 is defined under ASTM International, originating from United States, while BS 970 (Part 3) 403S17 is defined under British Standards (BS), originating from United Kingdom.
As per chemical composition, ASTM A240/A240M S40300 vs BS 970 (Part 3) 403S17 is a 86.9% 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 86.9%.
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property
ASTM A240/A240M S40300
BS 970 (Part 3) 403S17
Tensile Strength
>=485 MPa
Not specified
Yield Strength
>=205 MPa
Not specified
Elongation
>=25%
Not specified
Hardness
<=217 HB
Not specified
Condition
Plate, sheet and strip; yield by 0.2 percent offset
Not specified
Typical Applications
ASTM A240/A240M S40300
Pressure vessels and general applications (plate, sheet and strip)
BS 970 (Part 3) 403S17
Bright cold finished bars (cold drawn, turned or precision ground) for general engineering purposes, in straight lengths; ferritic stainless steel (Table 17)
Can ASTM A240/A240M S40300 Be Substituted With BS 970 (Part 3) 403S17?
ASTM A240/A240M S40300 and BS 970 (Part 3) 403S17 overlap closely enough on chemistry and mechanical properties that BS 970 (Part 3) 403S17 is often considered as a substitute for ASTM A240/A240M S40300 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 ASTM A240/A240M S40300 and BS 970 (Part 3) 403S17?
Both grades share a similar composition profile; see the specification table above for the exact chemistry and mechanical property values.
Can ASTM A240/A240M S40300 be substituted with BS 970 (Part 3) 403S17?
ASTM A240/A240M S40300 and BS 970 (Part 3) 403S17 overlap closely enough on chemistry and mechanical properties that BS 970 (Part 3) 403S17 is often considered as a substitute for ASTM A240/A240M S40300 in many applications. Always confirm the specific property range your application needs before substituting, and check with your supplier's mill certificate.