Welding Residual Stress Effect in Fracture Toughness

Steel plate thickness has increased with the growth of large structures like container ships. Thicker plates are linked to lower toughness and higher brittle fracture risk. This thickness effect remains poorly understood in welding contexts. Existing research has explored general fracture behavior but not welding-specific variables. The need to understand how welding processes influence crack propagation is clear. Prior studies have not fully addressed residual stress effects in thick plates. This gap motivated the investigation of two welding methods on thick steel plates. The study aims to clarify the role of welding residual stress in brittle fracture paths.

The study focuses on how welding residual stress affects brittle fracture in thick steel plates. It compares two welding processes to assess their impact on crack propagation. The goal is to determine how welding variables influence crack arrest toughness. The investigation uses 50 and 80 mm thick plates to model real-world applications. The study seeks to quantify the thickness effect on fracture behavior. It aims to clarify the role of residual stress in brittle crack paths. The purpose is to provide insights into welding practices for large structures. The findings may inform safer welding procedures for shipbuilding.

The study uses 80-mm-thick steel plates and two welding processes: flux cored arc welding and electron gas welding. Full-thickness weld joints are produced for analysis. Residual stress is measured in both welded joints. A temperature-gradient ESSO test is applied to evaluate crack propagation. Neutron science analysis is used to assess residual stress effects. The test clarifies how welding variables influence crack paths. The analysis is quantitative and focuses on brittle fracture behavior. The methods aim to compare the two welding processes systematically.

The study finds that welding residual stress significantly influences brittle crack propagation. Flux cored arc welding shows different stress patterns than electron gas welding. Thicker plates exhibit lower crack arrest toughness. The 80-mm plates show a higher likelihood of brittle fracture. Neutron analysis confirms residual stress effects on crack paths. The ESSO test reveals temperature-dependent crack behavior. Residual stress measurements highlight process-specific differences. The results suggest welding process choice affects fracture resistance.

The authors conclude that welding residual stress plays a key role in brittle fracture paths. The study shows that process choice affects crack propagation behavior. Thicker plates are more prone to brittle fracture due to residual stress. The findings suggest that welding methods influence fracture toughness. The results support the need for process-specific residual stress evaluations. The study does not claim that one welding process is superior. It emphasizes the importance of residual stress in fracture behavior. The conclusions are based on observed stress effects in thick plates.