Experimental Studies on Brittle Fracture in Welded Butt Joints with Defects at Welding End

摘要

Tensile tests were carried out on the welded butt joints with artificial through thickness defects to investigate brittle fracture behavior from the defects. In most specimens, a ductile crack propagated slightly from the bottom of the defect and then brittle crack initiated at the tip of the ductile crack. Brittle crack propagated from the weld bond into the heat-affected zone and then base metal of the stress continuity plate. The changes in the weld defect size significantly affected the welded joints performance experimentally, and the fracture strength of the welded joints was discussed by the fracture analysis.