Abnormal Grain Growth and Recrystallization in Al-Mg Alloy AA5182 Following Hot Deformation

作者：Chang Jung Kuei^*; Takata Ken; Ichitani Koji; Taleff Eric M

来源：Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science, 2010, 41A(8): 1942-1953.

DOI：10.1007/s11661-010-0213-7

Abnormally large grains have been observed in Al-Mg alloy AA5182 sheet material after forming at elevated temperature, and the reduced yield strength that results is a practical problem for commercial hot-forming operations. The process by which abnormal grains are produced is investigated through controlled hot tensile testing to reproduce the microstructures of interest. Abnormal grains are shown to develop strictly during static annealing or cooling following hot deformation; the formation of abnormal grains is suppressed during plastic straining. Abnormal grains grow by static abnormal grain growth (SAGG), which becomes a discontinuous recrystallization process when abnormal grains meet to form a fully recrystallized microstructure. Nuclei, which grow under SAGG, are produced during hot deformation by the geometric dynamic recrystallization (GDRX) process. The mechanism through which a normally continuous recrystallization process, GDRX, may be interrupted by a discontinuous process, SAGG, is discussed.

• 出版日期2010-8