Transverse Bend Test - A transverse bend test is useful in qualifying welders because it quite often reveals the presence of defects that are not detected in tension test. However, in this test, non-uniform properties along the length of the specimen can cause non-uniform bending.
An over matching weld metal strength may prevent the weld zone from conforming exactly to the bend die radius and may force the deformation out into the base metal, causing less than the desired elongation of the weld. With under matching weld strength, the specimen may tend to kink in the weld and there occurs more severe elongation in the weld. The specimen for transverse bend test is of the full thickness of the material at the welded joint and the upper and lower surfaces of the weld are dressed flush with the base metal surface.
