Chemical composition and mechanical properties of Q690R, a Chinese grade of low-temperature pressure vessel steel.
Q690R Approx. Grade Lookup Table
Q690R 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 |
Q690R 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 | |||
| Q690R | 10～80 | ≥690 | 800～920 | ≥16 | -20 | ≥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. | ||||||||