Q355NH Chemical composition and mechanical properties of  a Chinese grade  weathering steel

Q355NH Chemical Composition

Grage Chemical Composition(Quality Fraction)/%
C Si Mn P S Cu Cr Ni others
Q355NH ≤0 .16 ≤0 .5 0 . 5 ~
1.5
≤0 . 03 ≤0 . 03 0 . 25 ~
0 . 55
0 . 40 ~
0.80
≤0.65 a , b

Q355NH 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
Q355NH 355 345 335 325 490 ~ 630 22 22 21 20 a 2a 3a

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