Abstract: The fracture properties and behaviors of mathching strength and toughness of 16Mn welded joints are studied and analysed by means of the miniature deep notch test. The results show that under the conditions of high stress plastic fractures and high stress brittle fractures, the fracture strength of 16Mn steel welded joints is determined by the weld strength and joint plasticity and under the conditions of low stress brittle fractures, the resistance to joint fracture can be appraised on basis of the low-temperature impact toughness of weld metal. The plasticity of each part of the welded joints has an effect on fracture behaviors of joints and is one of the important foundations for appraising fracture of welded joints.

Key words: Fracture behavior, Fracture property, Impact toughness, Plasticity, Strength