一、前言由于焊接条件的限制,在工业上使用的焊接结构件中,多余夹杂物和质点的存在显然是不可避免的。焊缝金属中非金属夹杂物多数呈弥敞、细小颗粒存在(尺寸在1微米或更小)。它们有不同的来源;(1)焊接时进行反应的产物;(2)母材和填充金属过渡到焊缝中的夹杂物;(3)残余的熔渣质点和表面氧化物。众所周知,非金属夹杂物的存在往往破坏了焊缝金属的连续性,从而对其组织和性能有显著的影响。例如尖角形夹杂物是应力集中的根源,它能促使微裂纹萌生。又如明显减少焊缝断面的粗大熔渣夹杂 I. INTRODUCTION Due to the limitations of welding conditions, the presence of extra inclusions and particles in industrial welded structural parts is obviously inevitable. Weld metal non-metallic inclusions in most of the spacious, small particles (size of 1 micron or less). They have different origins; (1) products that are reacted during welding; (2) inclusions that migrate from parent metal and filler metal into the weld; and (3) residual slag particles and surface oxides. As we all know, the existence of non-metallic inclusions often undermine the continuity of the weld metal, which has a significant impact on the organization and performance. For example, sharp-pointed inclusions are the root cause of stress concentration, which can promote the initiation of micro-cracks. Another example is the significant reduction of coarse weld slag section inclusions