Microstructural aspects of additive friction stir welding of chrome-zirconium bronze

The work was undertaken to investigate the microstructural aspects of additive friction-stir welding (FSW) of chromium-zirconium bronze. This technology was applied for the renovation of the continuous steel casting crystallizer that was severely worn during long-term service. It was found that FSW provided significant grain refinement and coarsening of secondary particles and gave rise to the poorly developed fiber simple-shear texture. Based on microstructural observations, it was suggested that the grain structure evolution during FSW was governed by the continuous recrystallization but also involved the discontinuous recrystallization coupled with annealing twinning.