| Title |
The Study for Static Recrystallization Kinetics of AA 8091 Alloy |
| Authors |
이윤수(Yoon Soo Lee); 최병익(Byong Ick Choi); 오병문(Byung Moon Oh); 유연철(Yeon Chul Yoo) |
| Abstract |
After cold rolling of AA 8091 alloy by 5%∼30%, the static recrystallization kinetics were studied in the range of temperature from 350℃ to 500℃ with varying isothermal holding time from 1 to 5000 sec. It was observed that all recrystallized grains were nucleated at the grain boundaries which were formed during cold rolling and grown. The kinetics of recrystallization could be well described by Avrami equation, Y=1-exp(-ktⁿ) and the values of n were found to be in the range from 0.35 to 0.48 and those of k were known to be in the range from 8 × 10^(-2) to 3 × 10^(-1). It was found that the values of n were lower than those of any other Al alloys which have the value of 0.6, and therefore the recrystallization of AA 8091 alloy could be restricted by the precipitates of δ` and Al₃Zr. It was observed that the fast recrystallization rate was assisted by dislocation elimination, precitates coarsening and large amount of δ` resolution in Al matrix at higher temperatures than 450℃ and the effect of temperature on the recrystallization rate was more pronounced than that of prestrain on the rate at higher prestrains than 10 percents. |