Study on crack growth path of API-5L X80 welded joints based on inhomogeneous mechanical properties

Abstract

This study analyses the effect of inhomogeneous mechanical properties on the stress-strain field of crack tips and crack growth path at different locations of API-5L X80 welded joints. First, the inhomogeneous mechanical properties and microstructure of welded joints were analyzed in detail in this paper. Then, the ABAQUS subroutine USDFID was developed to ensure the continuity variation of the mechanical properties of the material in this region. Finally, the cracks in the welded joints were analysed using the extended finite element method (XFEM). The findings demonstrate that the inhomogeneous mechanical properties of welded joints give rise to crack growth path that are deflected towards the weld metal region, exhibiting the greatest rate of growth in this region.