铌微合金化Q345B钢板生产工艺开发与应用

为降低生产成本,通过分析钢板形成魏氏组织的原因以及中间坯厚度、道次变形量、低温轧制和控制冷却等对钢板组织晶粒度和性能的影响,探讨了采用铌微合金化代替钒生产不同厚度Q345B钢板的最佳生产工艺。工艺改进后,工序控制稳定,工序能力指数较高,冲击值平均提高78%,标准偏差由原来的23%缩小到5.96%,延伸率平均提高21%,标准偏差由原来的7.3%缩小到1.86%。

Development and Application of Production Process for Niobium Microalloy Q345B Plate

In order to reduce production cost, the best production process using niobium microalloy instead of vanadium to produce Q345B plates of different thickness is discussed through analyzing the reason of forming Widmannstaetten structure and the influences of slab thickness, the reduction in pass, low temperature rolling and control cooling etc on the grain size and the properties. After the process improvement, production control is stable, process capability index is higher, the impact value is increased by 78% averagely, the standard deviation is reduced to 5.96% from 23%, the elongation is increased by 21% averagely and the standard deviation is reduced to 1.86% from 7.3%