Abstract: Microstructure of the Zr-Sn-Nb-Fe zirconium alloy during processes of hot rolling and annealing, intermediate cold rolling and annealing, final cold rolling and annealing was observed and analyzed by means of optical microscope (OM) and scanning electron microscope (SEM). The results show that the microstructure of the alloy after hot rolling is distributed banded along the rolling direction, and the grains are coarsened, deformed seriously and broken. The alloy microstructure after the intermediate cold rolling and the finished product rolling is obviously refined as fine deformed ones distributed banded along the rolling direction. The recrystallization degree of the alloy after intermediate annealing and finished annealing is significantly higher than before, the grains are gradually homogenized and refined, with grain orientation difference gradually changes to a normal distribution. Finally, a fine, uniformly distributed and almost completely recrystallized microstructure is obtained, and the grain size is grade 12.

Key words: Zr-Sn-Nb-Fe zirconium alloy, rolling, heat treatment, grain microstructure