Minimal Match — 35% match
based on chemical composition and mechanical property overlap.
CSA G40.21 260WT (CSA G40.21-13 (R2023)) and ASTM A709 Grade HPS 70W (ASTM A709) are both steel grades.
Both fall under the Structural Steel (Corten / Weathering) category.
CSA G40.21 260WT is typically used for weldable structural steel with guaranteed charpy v-notch low-temperature toughness; secondary members, stair stringers, bracing in cold-climate service, while ASTM A709 Grade HPS 70W is commonly used for high-performance steel (hps) with enhanced atmospheric corrosion resistance and toughness; primary bridge girders and structural members in bridge construction.
CSA G40.21 260WT is defined under Canadian Standards Association (CSA), originating from Canada, while ASTM A709 Grade HPS 70W is defined under ASTM International, originating from United States.
As per chemical composition, CSA G40.21 260WT vs ASTM A709 Grade HPS 70W is a 66.1% match.
As per mechanical properties, the match is 0%.
Combined, this makes them a minimal match overall at 35%.
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property
CSA G40.21 260WT
ASTM A709 Grade HPS 70W
Tensile Strength
380-480 MPa
585 MPa min
Yield Strength
260 MPa min
485 MPa min
Elongation
23% min
19% min
Impact
27J at -20°C
Not specified
Hardness
Not specified
170-210 HB
Typical Applications
CSA G40.21 260WT
Weldable structural steel with guaranteed Charpy V-notch low-temperature toughness; secondary members, stair stringers, bracing in cold-climate service
ASTM A709 Grade HPS 70W
High-performance steel (HPS) with enhanced atmospheric corrosion resistance and toughness; primary bridge girders and structural members in bridge construction
Key Differences
ASTM A709 Grade HPS 70W specifies Mo which is not specified for CSA G40.21 260WT.
Can CSA G40.21 260WT Be Substituted With ASTM A709 Grade HPS 70W?
CSA G40.21 260WT and ASTM A709 Grade HPS 70W share some compositional similarity but differ enough that substitution should not be assumed. Review the differences above carefully, and consult the applicable standard or a metallurgist before using one in place of the other.
What is the difference between CSA G40.21 260WT and ASTM A709 Grade HPS 70W?
ASTM A709 Grade HPS 70W specifies Mo which is not specified for CSA G40.21 260WT.
Can CSA G40.21 260WT be substituted with ASTM A709 Grade HPS 70W?
CSA G40.21 260WT and ASTM A709 Grade HPS 70W share some compositional similarity but differ enough that substitution should not be assumed. Review the differences above carefully, and consult the applicable standard or a metallurgist before using one in place of the other.