400MPa级超细晶粒钢筋闪光对焊的组织及性能

MICROSTRUCTURE AND PROPERTY OF THE FLASH BUTT JOINTS IN 400 MPa ULTRA-FINE GRAIN STEEL

00MPa级超细晶粒钢筋是通过形变诱导形核及控轧控冷技术 ,生成微米级铁素体 ,从而提高钢的强度和韧性。本文结合焊接接头的微观金相观察和宏观性能试验 ,对 40 0MPa级超细晶粒钢筋闪光焊的适应性进行了研究。钢筋闪光焊接头具有良好的力学性能 ,接头HAZ不存在明显软化。只在焊缝心部区域出现局部软化 ,但少许的局部软化并不影响整个接头的性能。闪光对焊对于 40 0MPa级超细晶粒钢筋的焊接具有良好的适应性 。

The strength and toughness of 400 MPa ultra-fine grain reinforcing steel are greatly improved because of its microsize scale ferrite that is generated by TMCP and DIFT. In this paper the weldability of flash butt joints to 400 MPa ultra-fine reinforcing steel is investigated by using the metallographical observation and test of mechanical property. The joints of reinforcing steel after using flash butt welding show that there are only local soften regions in the inside of weld seam and no obvious soften regions in HAZ, and the whole joints have good mechanical property. The process of flash butt welding is appropriate for welding 400 MPa ultra-fine grain reinforcing steel, and good property of the joint is obtained.