Abstract
? 2022 Elsevier B.V.The hot deformation behavior in an AZ91 magnesium alloy was studied using Arrhenius model and Back-Propagation Artificial Neural Network (BP-ANN) approaches. The hot compression tests of AZ91 alloy were performed on the MMS-300 simulator at deformation temperatures and strain rates in the range of 473–623 K and 0.001 s?1- 1 s?1, respectively. The results indicated that the BP-ANN model has higher accuracy than Arrhenius model and the correlation coefficient is as high as 0.99341. The processing map is divided into three parts: machinable area (A), instability area I (INS I) (B) and instability area II (INS II) (C). The instability mode of areas B and C gradually changes from cracks to holes with the increase of temperature or the decrease of strain rate. The stable hot-deformation conditions with peak efficiency of power dissipation were concentrated in the range of 523 K, 0.01 s?1, 573 K, 0.01 s?1, 623 K, 0.001–1 s?1, respectively. With the increase of temperature, the deformation mechanism changed from twinning to dynamic recrystallization (DRX), which is discontinuous dynamic recrystallization (DDRX). Due to DRX,< 0001 > // CD texture intensity increased with the increase of temperature, and then decreased.
NSTL
Elsevier