1 the main purpose
q345 low-alloy high-strength structural steel plate series with thickness ranging from 6 to 200mm is widely used in steel structure construction, engineering machinery, mining machinery, heavy-duty vehicles, bridges, pressure vessels and other engineering structures, especially for weldability and toughness. highly important construction and mechanical engineering structures are required.
2 grades and standards
grade q345b/c/d/e; execution standard: gb/t 1591-2008 "low-alloy high-strength structural steel" (equivalent to japanese standard jisg3106-2008 grade sm490, european standard en10025-04 medium grade s355jr/j0/j2 /k2)
3 technical conditions of supply
3.1 product specifications
6~200×1500~4000×lmm
3.2 chemical composition
table 1 chemical composition%
牌号 | 等级 | c≤ | si≤ | mn≤ | p≤ | s≤ | cev≤63mm | cev>63mm |
q345 | b | 0.20 | 0.50 | 1.70 | 0.035 | 0.035 | 0.44 | 0.47 |
c | 0.18 | 0.50 | 1.70 | 0.030 | 0.030 | 0.44 | 0.47 | |
d | 0.18 | 0.50 | 1.70 | 0.030 | 0.025 | 0.44 | 0.47 | |
e | 0.18 | 0.50 | 1.70 | 0.025 | 0.020 | 0.44 | 0.47 |
note: b, c, d, e grade z-direction performance steel plates can be provided. if z-direction performance is required, the steel plate s content is to be carried out according to the gb/t5313-85 standard. the z-direction performance steel plate is marked with the z-direction level after the steel number.
3.3 力学性能
表2 力学性能
牌号 | 屈服强度rel,mpa, 不小于 | 抗拉强度rm,mpa | 断后伸长率a,%≥ | 冲击功,j kv2,纵向 | |||||
≥ 6~16 | > 16~40 | > 40~63 | > 63~80 | ≤40 | >40-80 | ℃ | ≥ | ||
q345b | 345 | 335 | 325 | 315 | 470~630 | 20 | 19 | 20 | 34 |
q345c | 21 | 20 | 0 | ||||||
q345d | 21 | 20 | -20 | ||||||
q345e | 21 | 20 | -40 |