轻量化脚手架钢管用超高强钢带开发

Development of UHSS Strips for Lightweight Scaffold Steel Pipes

为实现脚手架轻量化,通过对脚手架用管材Q355和替代材料Q620M的抗拉强度、抗压强度和抗弯强度的计算分析,提出在脚手架钢管外径不变、壁厚减薄的情况下,采用Q620M钢替代Q355钢,可实现减重25%。同时采用以钛析出强化为主的强化机制合金成分设计和TMCP工艺,实现了Q620M超高强热轧钢带低成本生产控制。生产实践表明,Q620M超高强度热轧钢带的强塑积超过15 GPa%;钢带经纵切、成型、高频焊接制管后,在未进行热处理的条件下,焊缝、热影响区和基体组织均匀,钢管强度和塑性指标均满足脚手架使用要求。

To achieve scaffold lightweight,tensile strength,compressive strength and bending strength of Q355 and alternative material Q620M are calculated.By replacing Q355 steel with Q620M steel while keeping the outer diameter of scaffold steel pipe constant and reducing the wall thickness,25% weight reduction can be achieved.Strengthening mechanism alloy composition design mainly based on titanium precipitation strengthening and TMCP were adopted to get low cost production control of Q620M ultra-high strength hot-rolled steel strip.Practice has shown that product of strength and ductility of Q620M ultra-high strength hot-rolled steel strip exceeds 15 GPa%.After slitting,forming and HF welding,the weld,HAZ and matrix structure are uniform without heat treatment,and the steel pipe strength and plasticity indicators meet the requirements for scaffold use.