Zr-Sn-Nb-Fe锆合金板材轧制及热处理过程中的晶粒组织演变

采用光学显微镜(OM)和扫描电镜(SEM)分析研究了Zr-Sn-Nb-Fe锆合金板材在热轧及退火→中间冷轧及退火→成品轧制及退火的全工艺流程中晶粒组织的演变规律。结果表明,热轧后合金组织沿轧制方向呈带状分布,晶粒粗大并破碎变形;中间冷轧和成品轧制后合金为沿轧制方向带状分布的细小形变组织,合金组织明显细化;中间退火和成品退火后合金中晶粒再结晶程度较热轧退火时明显提高,晶粒取向差逐渐向正态分布变化,晶粒组织也逐渐均匀化和细化,最终获得细小、均匀分布的完全再结晶晶粒组织,晶粒度12级。

Grain microstructure evolution in Zr-Sn-Nb-Fe zirconium alloy plates during rolling and heat treatment

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.