DYNAMIC RECRYSTALLIZATION BY HOT ROLLING TO REFINE GRAINS OF ZK60 ALLOY

摘要

ZK60 alloy was hot rolled at 400℃ to reduce its thickness by 80%, dynamic recrystallization occurred, reducing the grain size to ～2.6μm. This fine-grained structure exhibited super plastic elongation of up to 856% at 300℃ and a strain rate of 10~(-4)/s. A variant thermo-mechanical processing route yielded fine-grained structures with grain size of ～2.1 μm. The advantages of both static and dynamic recrystallization were exploited by rolling at two temperatures, 200℃ and 400℃, sequentially, reducing the thickness by 80% as achieved by the aforementioned isothermal rolling.