On the bimodal grain growth in zirconium grade 702 alloy

This study is built upon previously published work that involved bimodal grain growth in cold worked and annealed samples of zirconium 702 alloy. Similar to the earlier study, the new zirconium 702 alloy samples were rolled and bent at different percentages of cold work and then annealed at 1375 °F. While bimodal grain growth did occur in the previous samples under bending when annealed above 1275 °F, no bimodal grain growth was observed in any of the new samples. This result is attributed to the different weight percent of alloying elements in the two samples. Additionally, a recovery anneal was performed on the old samples in an effort to inhibit grain growth in the alloy system. Although the recovery anneal did not prevent bimodal grain growth, it did significantly reduce the degree to which it occurred.