锁底结构焊缝的射线底片线状影像识别方法研究

Study on the identification method of linear imaging in X-ray negative of the butt-lap joints

以实际生产过程中常用的两种锁底结构焊缝为研究对象,对锁底焊缝X射线底片存在局部线状成像处截取金相试样,通过光学显微镜观察截取的金相试样,研究局部线状成像的具体原因。结果表明,锁底1结构焊缝X射线底片局部线状成像通常因结构形式导致的搭接面存在间隙,液体熔池沿此间隙流动致使最终焊缝出现局部成像不良;锁底2结构焊缝X射线底片局部线状成像的原因是焊缝根部局部出现内凹成形。

The welds of two kinds of common butt-lap joint commonly used in the actual production are taken as the objects ,and the metallographic specimens are taken from the welds where the partial linear-imaging exists in their X-ray negatives. By optical microscope ,these metallographic specimens are observed to study the reason of partial linear-imaging. The results show that the liquid metal in molten pool flowing through the gap made by the structure of lap joints causes bad partial linear-imaging in X-ray negatives of butt-lap joint 1 ; And the partial linear-imaging in X-ray negatives of butt-lap joint 2 is usually caused by concave-inward forming in the partial root of welds.