|About this Abstract
||2023 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Can We Make an Electron Beam Weld ‘Disappear’?
||Kirstie Bruce, Mark Taylor, Jonathan W Fellowes, Luke D Burling, John A Francis, Ed J Pickering
|On-Site Speaker (Planned)
A novel post-weld heat treatment (PWHT) for electron beam welded pressure vessel steel, SA508 Grade 4N, was developed with the aim of fully homogenising microstructure and properties across the material, essentially making the weld disappear. A number of conventional and novel PWHT schedules were applied, including full re-austenitisation, quench and temper. Hardness was successfully homogenised across the parent and weld in all heat treatments involving re-austenitisation (860°C), but compositional microsegregation in the fusion zone was only removed by applying a homogenisation step at 1200°C. Nevertheless, even after the most severe PWHT, the weld area remained visible optically after etching. Austenite grain growth kinetics and continuous cooling transformation behaviour in the fusion zone and parent material was also studied to determine whether these regions are fundamentally different.
||Iron and Steel, Joining, Phase Transformations