Q265GNH Chemical composition and mechanical properties of  a Chinese grade  weathering steel

Q265GNH Chemical Composition

Grage Chemical Composition(Quality Fraction)/%
C Si Mn P S Cu Cr Ni others
Q265GNH ≤0 . 12 0 . 10 ~
0 . 40
0 . 20 ~
0 . 50
0 . 07 ~
0 . 12
≤0 . 020 0 . 20 ~
0 . 45
0 . 30 ~
0 . 65
0 . 25 ~
0 . 50 e
a , b

ᵃ To improve the properties of steel, one or more trace alloying elements may be added: Nb 0.015%~0.060%, V 0.02%~0.12%, Ti 0.02%~0.10%, Alt ≥0.020%. When the above elements are used in combination, at least one element should be ensured to meet the lower limit of the above chemical composition.

ᵇ The following alloying elements can be added: Mo≤0.30%, Zr≤0.15%.

ᶜ The total amount of the three alloying elements Nb, V, and Ti added should not exceed 0.22%.

ᵈ Through negotiation between the supplier and the buyer, the sulfur content may not exceed 0.008%. 

ᵉ Through negotiation between the supply and demand parties, a lower limit for Ni content may not be required.

ᶠ Through negotiation between the supply and demand parties, the content of C may not exceed 0.15%.

7.1.2 The permissible deviations in the chemical composition of finished steel products shall comply with the provisions of GB/T 222.

7.2 Smelting methods:The steel is smelted in a converter or electric furnace and is killed steel. Unless otherwise specified by the buyer, the smelting method shall be selected by the supplier.

7.3 Delivery status:Hot-rolled steel is delivered in hot-rolled, controlled-rolled, or normalized condition. Steel grades Q460NH, Q500NH, and Q550NH can be delivered in quenched and tempered condition. Cold-rolled steel is generally delivered in annealed condition.

Q265GNH Mechanical properties and processing properties

Grade Tensile Test   a 180 °Bending test mandrel diameter
Lower yield strength ReL  ≥ Tensile Strength
Rm
Elongation after fracture A/%≥
≤16 >16 ~40 >40 ~60 >60 ≤16 >16~40 >40~60 >60 ≤6 >6 ~16 >16
Q265GNH 265 - ≥410 27 - - a -    -

Note: 'a' represents the steel thickness.
When a yield plateau is not evident, Rp0.2 may be used.