Minimal Match — 35% match
based on chemical composition and mechanical property overlap.
GB/T 1591 Q355C (GB/T 1591:2018) and CSA G40.21 400A (CSA G40.21-13 (R2023)) are both steel grades.
Both fall under the Structural Steel category.
GB/T 1591 Q355C is typically used for general structure for engineering (plates, strips, bars and sections), while CSA G40.21 400A is commonly used for atmospheric corrosion-resistant (weathering) structural steel; exposed bridge girders and structural members where high strength and weathering resistance are both needed.
GB/T 1591 Q355C is defined under Guobiao Standards (GB/T), originating from China, while CSA G40.21 400A is defined under Canadian Standards Association (CSA), originating from Canada.
As per chemical composition, GB/T 1591 Q355C vs CSA G40.21 400A is a 78.6% match.
As per mechanical properties, the match is 18.3%.
Combined, this makes them a minimal match overall at 35%.
Other Structural Steel Grades to Compare With GB/T 1591 Q355C:
Matched by chemical composition and mechanical properties, not a formal equivalence claim. Always verify against the applicable standard before substitution.
Mechanical Properties
Property
GB/T 1591 Q355C
CSA G40.21 400A
Tensile Strength
470-630 MPa
520-670 MPa
Yield Strength
>=355 MPa
400 MPa min
Elongation
>=22%
17% min
Condition
Hot-rolled (as-rolled), nominal thickness or diameter up to 16 mm for yield; tensile strength for up to 100 mm; elongation longitudinal, up to 40 mm
Not specified
Impact
Not specified
27J at 0°C
Typical Applications
GB/T 1591 Q355C
General structure for engineering (plates, strips, bars and sections)
CSA G40.21 400A
Atmospheric corrosion-resistant (weathering) structural steel; exposed bridge girders and structural members where high strength and weathering resistance are both needed
Key Differences
GB/T 1591 Q355C specifies Cr, Ni, N which are not specified for CSA G40.21 400A.
Can GB/T 1591 Q355C Be Substituted With CSA G40.21 400A?
GB/T 1591 Q355C and CSA G40.21 400A 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 GB/T 1591 Q355C and CSA G40.21 400A?
GB/T 1591 Q355C specifies Cr, Ni, N which are not specified for CSA G40.21 400A.
Can GB/T 1591 Q355C be substituted with CSA G40.21 400A?
GB/T 1591 Q355C and CSA G40.21 400A 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.