When the excitation current increases to 20A, the number of pores sharply decreases, the grains are fine and uniform, and the particle reinforced phases are uniformly distributed in the weld.
当激励电流提高到20A时，气孔数量急剧减少，焊缝晶粒细小均匀，颗粒状增强相弥散分布；
2
The theatre steel roof of Henan Provincial Art Centre is a complex structural system, comprised of the in-plane penetrated weld pipe truss and three reinforced concrete elements underneath.