Risk based analysis of temperature and time effects on brittle fracture of A-387 Gr. B welded joint

Abstract Risk based analysis of temperature and time effects on fracture toughness values is applied to different regions of a welded joint made of low-alloyed Cr-Mo steel A-387 Gr. B, designed for high temperature applications. Heterogeneity of microstructure and properties of welded joint is evaluated by testing standard 3BP specimens with crack tip located at different regions of a joint, including the base metal (BM), weld metal (WM) and heat-affected-zone (HAZ). Experiments were performed both at the room temperature and at design working temperature, 540°C. Based on these results, fracture toughness values are determined and used for risk based analysis, including risk matrix presentation as the basis for decision making process.