Close Alternative — 78.3% match
based on chemical composition and mechanical property overlap.
GB/T 1591 Q420B (GB/T 1591:2018) and GB/T 1591 Q420NC (GB/T 1591:2018) are both steel grades.
Both fall under the Structural Steel category.
GB/T 1591 Q420B is typically used for general structure for engineering (plates, strips, bars and sections), while GB/T 1591 Q420NC is commonly used for general structure for engineering (plates, strips, bars and sections).
GB/T 1591 Q420B is defined under Guobiao Standards (GB/T), originating from China, while GB/T 1591 Q420NC is defined under Guobiao Standards (GB/T), originating from China.
As per chemical composition, GB/T 1591 Q420B vs GB/T 1591 Q420NC is a 84.1% match.
As per mechanical properties, the match is 66.7%.
Combined, this makes them a close alternative overall at 78.3%.
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 Q420B
GB/T 1591 Q420NC
Tensile Strength
520-680 MPa
520-680 MPa
Yield Strength
>=420 MPa
>=420 MPa
Elongation
>=20%
>=19%
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
Normalized or normalizing rolled, nominal thickness or diameter up to 16 mm (tensile strength: up to 100 mm)
Typical Applications
GB/T 1591 Q420B
General structure for engineering (plates, strips, bars and sections)
GB/T 1591 Q420NC
General structure for engineering (plates, strips, bars and sections)
Key Differences
GB/T 1591 Q420NC specifies Al which is not specified for GB/T 1591 Q420B.
Can GB/T 1591 Q420B Be Substituted With GB/T 1591 Q420NC?
GB/T 1591 Q420B and GB/T 1591 Q420NC are a close alternative rather than a direct substitute. Some properties overlap well, but check the specific chemistry and mechanical rows above against your application's requirements before treating them as interchangeable.
What is the difference between GB/T 1591 Q420B and GB/T 1591 Q420NC?
GB/T 1591 Q420NC specifies Al which is not specified for GB/T 1591 Q420B.
Can GB/T 1591 Q420B be substituted with GB/T 1591 Q420NC?
GB/T 1591 Q420B and GB/T 1591 Q420NC are a close alternative rather than a direct substitute. Some properties overlap well, but check the specific chemistry and mechanical rows above against your application's requirements before treating them as interchangeable.