Synchrotron Diffraction Residual Strain Scanning in Friction Stir Welds as a Function of Process Conditions

摘要

This paper presents residual stress state data for friction stir welds (FSW) in AA5083-^sH321 alloy as a function of varying process parameters using synchrotron X-ray diffraction measurements. Understanding of residual stress magnitudes and origins is essential in order to advance our ability to predict optimised process conditions for making FSW joints. This process optimisation arises from linking the residual stress state with energy input into the weld and then linking these with mechanical and dynamic performance. In this work, a characteristic 'force footprint', obtained during automated and instrumented welding (1) is used as a linking tool for forces, energy, process conditions and performance. This linking of fundamental process parameters such as tool rotational speed and translation speed along the joint with weld properties can provide significant insights relevant to understanding and modelling of the process-structureperformance relationship for FS welds. Residual stresses are a key component in this bridging exercise and synchrotron diffraction strain scanning allows the acquisition of large datasets in a relatively short time.