Micro damage and fracture of SUS304 stainless steel under uniaxial tension

Abstract

The SUS304 stainless steel is widely used in many industries, and the prediction and detection of fracture tendency in these stainless steel applications are very important for their safety and serviceability. The ductile fracture is caused by micro damage and its accumulation, whose mechanism can be described by the micro void nucleation, growth and final extension to failure. The nucleation, growth and extension of the micro voids are related with the movement of the dislocations. In this paper, the optic microscope, X-ray diffraction and scanning electron microscope were used to observe the changes of the sample during uniaxial tensile tests, and analyse the relationship between micro void and dislocation density, and finally establish a dislocation density-strain model. This model provides a new idea for non-destructive testing, which can be applied to the early identification of fracture tendency.