Although the ferrite grains in the HAZ coarsened in all reported welding methods in which maximum temperatures are above liquidus of UFG steels,the HAZ softening were restrained.

• 系统分析了超细晶粒钢焊接接头的组织特征和焊接性,对超细晶粒钢焊接方法进行了新的分类组织保存型焊接工艺与同性能焊接工艺。