Abstract
Linear friction welding (LFW) is an advanced joining technology used for manufacturing and repairing complex assemblies like blade integrated disks (blisks) of aeroengines. This paper presents an integrated multiphysics computational modelling for predicting the thermomechanical-microstructural processes of IN718 alloy (at the component-scale) during LFW. Johnson–Mehl–Avrami-Kolmogorov (JMAK) model was implemented for predicting the dynamic recrystallisation of γ grain, which was coupled with thermomechanical modelling of the LFW process. The computational modelling results of this paper agree well with experimental results from the literature in terms of γ grain size and weld temperature. Twenty different LFW process parameter configurations were systematically analysed in the computations by using the integrated model. It was found that friction pressure was the most influential process parameter, which significantly affected the dynamic recrystallisation of γ grains and weld temperature during LFW. The integrated multiphysics computational modelling was employed to find the appropriate process window of IN718 LFW.
Highlights
Linear friction welding (LFW) is an advanced energy-efficient solid-state joining technology, which has important application in the manufacture of critical engineering components such as in the aerospace industry
In this study, integrated multiphysics computational modelling for LFW process was developed by sequentially coupling a thermomechanical model with a microstructural model
Elastic and plastic deformation of weld, and dynamic recrystallisation are in the modelling, which predicts the results of LFW of Inconel 718 (IN718) in terms of such as weld temperature, plastic strain, volume fraction of recrystallised γ grains, and resulting γ grain size as well as axial shortening of the overall weld
Summary
Linear friction welding (LFW) is an advanced energy-efficient solid-state joining technology, which has important application in the manufacture of critical engineering components such as in the aerospace industry. The δ phase has the same composition as the γ" phase, precipitates at the grain boundaries, and can prevent grain boundary migration [12,13,14] These primary and secondary phases of IN718 undergo significant microstructural change during thermomechanical processing, due to elevated temperature and significant material deformation, which can significantly affect the mechanical properties of manufactured components. Mary and Jahazi noted that dynamic recrystallisation and dynamic recovery of γ grains occur simultaneously with the loss of the δ phase in IN718 weld joint during LFW [16] They reported that γ grains within ± 1 mm distance from the friction interface were three times smaller than those of the parent material (16 μm) because DRX occurred during LFW [16].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
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
