Strong Match — 98.9% match
based on chemical composition and mechanical property overlap.
GB/T 1591 Q690MD (GB/T 1591:2018) and GB/T 1591 Q690MC (GB/T 1591:2018) are both steel grades.
Both fall under the Structural Steel category.
GB/T 1591 Q690MD is typically used for general structure for engineering (plates, strips, bars and sections), while GB/T 1591 Q690MC is commonly used for general structure for engineering (plates, strips, bars and sections).
GB/T 1591 Q690MD is defined under Guobiao Standards (GB/T), originating from China, while GB/T 1591 Q690MC is defined under Guobiao Standards (GB/T), originating from China.
As per chemical composition, GB/T 1591 Q690MD vs GB/T 1591 Q690MC is a 98.4% match.
As per mechanical properties, the match is 100%.
Combined, this makes them a strong match overall at 98.9%.
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 Q690MD
GB/T 1591 Q690MC
Tensile Strength
770-940 MPa
770-940 MPa
Yield Strength
>=690 MPa
>=690 MPa
Elongation
>=14%
>=14%
Condition
Thermomechanical processed (TMCP), nominal thickness or diameter up to 16 mm (tensile strength: up to 40 mm)
Thermomechanical processed (TMCP), nominal thickness or diameter up to 16 mm (tensile strength: up to 40 mm)
Typical Applications
GB/T 1591 Q690MD
General structure for engineering (plates, strips, bars and sections)
GB/T 1591 Q690MC
General structure for engineering (plates, strips, bars and sections)
Can GB/T 1591 Q690MD Be Substituted With GB/T 1591 Q690MC?
GB/T 1591 Q690MD and GB/T 1591 Q690MC overlap closely enough on chemistry and mechanical properties that GB/T 1591 Q690MC is often considered as a substitute for GB/T 1591 Q690MD 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 GB/T 1591 Q690MD and GB/T 1591 Q690MC?
Both grades share a similar composition profile; see the specification table above for the exact chemistry and mechanical property values.
Can GB/T 1591 Q690MD be substituted with GB/T 1591 Q690MC?
GB/T 1591 Q690MD and GB/T 1591 Q690MC overlap closely enough on chemistry and mechanical properties that GB/T 1591 Q690MC is often considered as a substitute for GB/T 1591 Q690MD in many applications. Always confirm the specific property range your application needs before substituting, and check with your supplier's mill certificate.