Abstract
An innovative finite element modelling approach has been tested to investigate the effects of weld repair of thin sheets of titanium alloy, taking into account a pre-existing stress field in the components. In the case study analysed, the residual stress fields due to the original welds are introduced by means of a preliminary sequentially-coupled thermo-mechanical analysis and considered as pre-existing stress in the sheets for the subsequent repair weld simulation. Comparisons are presented between residual stress predictions and experimental measurements available from the literature, with the aim of validating the numerical procedure. As a destructive sectioning technique was used in the reference experimental measurements, an investigation is also presented on the use of the element deactivation strategy when adopted to simulate material removal. Although the numerical tool is an approximate approach to simulate the actual material removal, the strategy appears to predict a physical strain relaxation and stress redistribution in the remaining part of the component. The weld repair modelling strategy and the element deactivation tool adopted to simulate the residual stress measurement technique are shown to predict residual stress trends which are very well correlated with experimental findings from the literature.
Highlights
Weld repair is a specific application of fusion welding processes that has been adopted across industrial fields to correct anomalies that may arise in structural components from the component manufacturing processes
As the anomaly is relatively small compared to the weld length, it is assumed this has a negligible effect on the residual stress distribution caused by the original joining process
The positive and negative gradients in trends of temperature are a clear effect of the heat source pass and cooling down
Summary
Weld repair is a specific application of fusion welding processes that has been adopted across industrial fields to correct anomalies that may arise in structural components from the component manufacturing processes. Weld repair can be used where anomalies are introduced through the service life of the component, helping to extend the operative life of components. As these are extensively adopted in the nuclear, petrochemical and power generation industries, the main volume of research in this area is related to either aged or deteriorated materials in the case of pipe geometries [1,2,3,4]. Based on finite element (FE) analysis, the numerical approach is a powerful and well-proven tool for predicting the macro-scale effects of both arc and beam welding processes.
Sign-in/Register to view highlights & summary 
Accepted Version (
Free)
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call