Development of a numerical procedure for assessing the fracture resistance of materials for pressure pipelines using the ring specimens

The main topic of this work is evaluation and enhancement of procedure for fracture mechanics parameters determination in thin-walled pipelines under extreme load conditions, focusing on the impact of non-standard specimen geometries and additive manufacturing techniques. In addition to mechanical testing, we utilized finite element analysis (FEA) with the Simulia Abaqus software to further understand the influence of geometrical ratios and variations in specimen design, such as the cylindrical shape and the presence/size of one or two sharp stress concentrators. The main results extracted from numerical calculations are quantities needed for determination of the J-integral: stress intensity factor KI, plastic geometry factor η and crack propagation correction factor γ. A generally linear relationship is obtained between the calculated parameters and the geometric ratio (a/W), suggesting that the variations in specimen width, wall thickness, and cross-section have a quantifiable impact on the material`s fracture behavior. This integrated methodology not only provides a comprehensive understanding of the fracture mechanics of thin-walled pipelines but also demonstrates the procedure's potential for practical implementation in structural assessment and material development for industrial applications.