Close Alternative — 77.6% match
based on chemical composition and mechanical property overlap.
GB/T 3077 40B (GB/T 3077:2015) and GB/T 3077 50B (GB/T 3077:2015) are both steel grades.
Both fall under the Alloy Steel category.
GB/T 3077 40B is typically used for hot-rolled or forged structural alloy steel bars, while GB/T 3077 50B is commonly used for hot-rolled or forged structural alloy steel bars.
GB/T 3077 40B is defined under Guobiao Standards (GB/T), originating from China, while GB/T 3077 50B is defined under Guobiao Standards (GB/T), originating from China.
As per chemical composition, GB/T 3077 40B vs GB/T 3077 50B is a 91.4% match.
As per mechanical properties, the match is 50%.
Combined, this makes them a close alternative overall at 77.6%.
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 3077 40B
GB/T 3077 50B
Tensile Strength
>=785 MPa
>=785 MPa
Yield Strength
>=635 MPa
>=540 MPa
Elongation
>=12%
>=10%
Hardness
<=207 HB
<=207 HB
Condition
Quenched and tempered, test sample 25 mm; hardness is for bars delivered annealed or high temperature tempered
Quenched and tempered, test sample 20 mm; hardness is for bars delivered annealed or high temperature tempered
Typical Applications
GB/T 3077 40B
Hot-rolled or forged structural alloy steel bars
GB/T 3077 50B
Hot-rolled or forged structural alloy steel bars
Can GB/T 3077 40B Be Substituted With GB/T 3077 50B?
GB/T 3077 40B and GB/T 3077 50B 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 3077 40B and GB/T 3077 50B?
Both grades share a similar composition profile; see the specification table above for the exact chemistry and mechanical property values.
Can GB/T 3077 40B be substituted with GB/T 3077 50B?
GB/T 3077 40B and GB/T 3077 50B 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.