中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 20 No. 7 July 2010 |
isothermal annealing
(1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Department of Mechanical Engineering and Intelligent Systems, University of Electro Communications,
Tokyo 182-8585, Japan)
Abstract:The static recrystallization of hot-deformed magnesium alloy AZ31 during isothermal annealing was studied at temperature of 503 K by optical and SEM/EBSD metallographic observation. The grain size change during isothermal annealing is categorized into three regions, i.e. an incubation period for grain growth, rapid grain coarsening, and normal grain growth. The number of fine grains per unit area, however, decreases remarkably even in incubation period. This leads to grain coarsening taking place continuously in the whole period of annealing. In contrast, the deformation texture scarcely changes even after full annealing at high temperatures. It is concluded that the annealing processes operating in hot-deformed magnesium alloy with continuous dynamic recrystallized grain structures can be mainly controlled by grain coarsening without texture change, that is, continuous static recrystallization.
Key words: magnesium alloy; AZ31; annealing; continuous recrystallization; grain growth; texture