Predicting residual stress in a 316L electron beam weld joint incorporating plastic properties derived from a crystal plasticity finite element model. (February 2023)

• Record Type: Journal Article
• Authors: Mokhtarishirazabad, Mehdi; McMillan, Martin; Vijayanand, V.D.; Simpson, Chris; Agius, Dylan; Truman, Christopher; Knowles, David; Mostafavi, Mahmoud
• Is Part Of: International journal of pressure vessels and piping. Volume 201(2023)
• Publication Date: 2023-02
• Subjects: Electron beam welding -- Residual stress -- Crystal plasticity model -- X-ray diffraction; Pressure vessels -- Periodicals; Pipe -- Periodicals; Récipients sous pression -- Périodiques; Tuyaux -- Périodiques; Pipe; Pressure vessels; Periodicals; 681.76041
• DOI: 10.1016/j.ijpvp.2022.104868
• Languages: English
• ISSNs: 0308-0161

Abstract

Abstract: Electron beam welding is an advanced joining technique which induces narrow weld region with minimal heat affected zone and weld-induced distortion. This reduces residual stresses in the joints which can be detrimental to structural performance of components in safety critical industries. Being an autogenous process, electron- beam welding generates a highly textured, columnar microstructure in the weld zone which have distinct properties when compared to the parent material region. Determining mechanical properties of the weld material assists in accurate assessment of the joint. However, extracting weld material specimens to determine plastic properties becomes increasingly cumbersome in thinner weld joints. An alternate approach has been demonstrated in this work wherein mechanical properties were derived using the weld microstructure in a crystal plasticity finite element (CPFE) framework. The initial calibration of the CPFE parameters was done using experimental data from thick weldment. These calibrated values were used to obtain the elastic and elastic-plastic properties of thinner weld materials by deforming corresponding synthetic microstructures whose attributes were determined by Electron Backscatter Diffraction analysis. The resultant properties were incorporated in a finite element (FE) based weld simulation to determine the residual strain. These results were compared with the residual strain data obtained using X-ray diffraction and good agreement was observed. Graphical abstract: Image 1 Highlights: Distribution of residual stresses in electron beam weldments is predicted and compared with experimental measurements. The experimental work uses a variety of techniques to build the full residual stress tensor of electron beam welds. A new approach has been employed in the model to implement a length-scale dependent hardening. Better agreement between the experimental and the simulated residual stresses in some of the weldments achieved.