Friction Stir Processing Of Aluminum Fusion Welds

摘要

Friction stir processing (FSP) is used to modify the microstructure and the resultant properties of fusion welded aluminum alloys. Non-heat treatable 5083-H321 Al is subjected to FSP at the fusion weld toe, crown, and heat-affected zone locations. FSP affects both the local fusion weld microstructure and residual stresses. To understand the influence of FSP on fusion welds, the effect of different FSP processing approaches is investigated. The morphology and spatial distribution of precipitates and grains are examined through optical microscopy, scanning electron microscopy, and transmission electron microscopy. The relationships between microstructure and properties such as strength and ductility are discussed. Consideration is given to the local properties in transition regions between the different microstructures, i.e., fine grain FSP zone, cast fusion zone, and parent metal.