气保焊丝用H11Mn2SiA热轧盘条的研制与开发

分析气保焊丝用H11Mn2SiA热轧盘条中合金元素对焊接性能的影响,设计盘条的化学成分和生产工艺流程,在Gleeble-1500热模拟机上测定H11Mn2SiA动态CCT曲线。对比盘条在870,850,820℃吐丝温度下的金相组织和力学性能,结果表明,当盘条在斯太尔摩线冷却速度不大于1℃/s时,盘条能够完成平衡转变,且对盘条的金相组织和力学性能影响不大,铁素体晶粒度均为8.5级。分析不同碳质量分数对盘条力学性能的影响,结果表明,当碳质量分数不大于0.08%时能有效降低盘条抗拉强度。对碳质量分数为0.07%,吐丝温度870℃,冷速为0.51℃/s条件下生产的焊丝进行焊接试验评定,熔敷金属力学性能全部满足要求,抗拉强度540 MPa,-30℃平均V型冲击功67 J,焊接性能优良。

Research and development of H11Mn2SiA hot rolled wire rod for gas shielded welding wire

To analyze the influence of alloy element in HllMn2SiA hot rolled wire rod for gas shielded welding wire on welding performance. The wire rod chemical composition and production process flow was designed. The dynamic CCT curve of H11Mn2SiA was investigated with thermal simulation machine of Gleeble -1500. The microstructure and mechanical properties of wire rod laying temperature 870, 850, 820 ℃ were compared. Results show ： when cooling speed of wire rod in Stelmor line is less than 1 ℃/s, the wire rod can complete balance transformation, which has little influence on wire rod microstructure and mechanical properties, the grain size of ferrite is 8.5 grade. The influence of different carbon mass fraction on wire rod mechanical properties is analyzed, results show that wire rod tensile strength can be decreased effective- ly when carbon mass fraction is less than 0.08%. The welding wire produced by the following process such as carbon mass fraction 0.07% , wire rod laying temperature 870 ℃, calculating cooling speed 0.51 ℃/s was welding test evaluated, the mechanical properties of melting metal meet requirements fully, tensile strength is 540 MPa, - 30 ℃ V type impact energy is 67 J, welding properties are good.