Chemical composition and mechanical properties of Q580DR, a Chinese grade of cryogenic pressure vessel steel.
Q580DR Approximate Grade Lookup Table

Q580R Chemical Composition

Grade Chemical Composition(Quality Fraction)/%
C≤ Si Mn P≤ S≤ Cu≤ Ni Cr≤ Mo Nb≤ V Ti≤ B≤ Pcm≤
Q580DR 0.10 0.15~0.40 1.20~1,60 0.015 0.005 0.25 0.30~0.60 0.50 0.10~0.30 0.05 0.02~0.06 0.03 0.0020 0.25

Q580R Mechanical properties and processing properties

Grade Thickness mm Tensile test Impact test 180°Bending test b=2a
Lower yield strengthᵃ
ReL/MPa		 Tensile strengthRm/MPa Elongation after fracture A/% Temperature
℃		 Impact absorption energy KV₂/J Lateral expansion value LE/mm
Q580DR 10～50 ≥580 690～820 ≥16 -50 ≥80 ≥0.64 D=3a
Note: D is the diameter of the bending indenter; b is the width of the sample; a is the thickness of the sample.
ᵃ When the yielding phenomenon is not obvious, the specified plastic elongation strength Rp0.2 is adopted.