电磁锤随焊锤击控制焊接应力变形新工艺

通过用电磁锤锤头对焊后尚处于高温状态的焊趾和焊缝区金属施加一定频率的锤击力,迫使焊趾处的金属向焊缝中心流动,抵消致裂拉伸应变,达到防止焊接热裂纹的目的;同时使焊缝金属在纵向和横向充分延展,降低了焊接残余应力.试验结果表明:该工艺简单可靠、轻便灵活,不但能控制焊接变形、防止焊接热裂纹的产生,而且能使焊缝组织均匀细化;与未锤击时相比,试件焊缝纵向残余应力平均下降了约90%.

New Welding Technology with Trailing Peening for Controlling Welding Stress and Distortion by Electromagnetic Hammer

By peening, head, impulsive force with a certain frequency was applied to the metal of the weld seam and the weld toe when they were still hot after welding. Impulsive force compeled the metal of the weld toe to flow toward the central line of the weld seam, and counteracted the tensile strain which prevented hot crocking of welding. At the same time, the impulsive force stretched the longitudinal and transverse compressive strain in the weld, and relieved welding residual stress. The experiments show that the technology is simple and reliable, portable and flexible, it can control welding distortion and prevent hot crack from producing, and make crystalline grain thin. Compared with the traditional welding, longitudinal residual stresses drop 90% on average.