Chemical composition and mechanical properties of Q690R, a Chinese grade of low-temperature pressure vessel steel.
Q690R Approx. Grade Lookup Table

Chemical Composition

Grade Chemical Composition(Quality Fraction)/%
C≤ Si Mn P≤ S≤ Cu≤ Ni Cr≤ Mo Nb≤ V Ti≤ B≤ Pcm≤
Q690R 0.13 0.15~0.40 1.00~1.60 0.015 0.005 0.25 0.30~1.00 0.80 0.20~0.80 0.06 0.02~0.06 0.03 0.0020 0.30

Mechanical properties and processing properties

Grade Thickness mm Tensile test Impact test 180°Bending test b=2a
Lower yield strength
ReL/MPa
Tensile strengthRm/MPa Elongation after fracture A/% Temperature ℃ Impact absorption energy KV₂/J Lateral expansion value LE/mm
Q690R 10~80 ≥690 800~920 ≥16 -20 ≥80 ≥0.64 D=3a