Minimal Match — 35% match
based on chemical composition and mechanical property overlap.
GB/T 1591 Q420MD (GB/T 1591:2018) and CSA G40.21 400W (CSA G40.21-13 (R2023)) are both steel grades.
Both fall under the Structural Steel category.
GB/T 1591 Q420MD is typically used for general structure for engineering (plates, strips, bars and sections), while CSA G40.21 400W is commonly used for heavy structural fabrication, bridges, offshore platforms, cranes, pressure vessels, mining equipment..
GB/T 1591 Q420MD is defined under Guobiao Standards (GB/T), originating from China, while CSA G40.21 400W is defined under Canadian Standards Association (CSA), originating from Canada.
As per chemical composition, GB/T 1591 Q420MD vs CSA G40.21 400W is a 61.8% match.
As per mechanical properties, the match is 47.1%.
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
GB/T 1591 Q420MD
CSA G40.21 400W
Tensile Strength
520-680 MPa
520-690 MPa
Yield Strength
>=420 MPa
400 MPa min
Elongation
>=19%
Not specified
Condition
Thermomechanical processed (TMCP), nominal thickness or diameter up to 16 mm (tensile strength: up to 40 mm)
Not specified
Typical Applications
GB/T 1591 Q420MD
General structure for engineering (plates, strips, bars and sections)
GB/T 1591 Q420MD specifies Nb, V, Ti, Cr which are not specified for CSA G40.21 400W.
Can GB/T 1591 Q420MD Be Substituted With CSA G40.21 400W?
GB/T 1591 Q420MD and CSA G40.21 400W 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 Q420MD and CSA G40.21 400W?
GB/T 1591 Q420MD specifies Nb, V, Ti, Cr which are not specified for CSA G40.21 400W.
Can GB/T 1591 Q420MD be substituted with CSA G40.21 400W?
GB/T 1591 Q420MD and CSA G40.21 400W 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.