Deformation homogeneity in accumulative back extrusion processing of AZ31 magnesium alloy
Deformation homogeneity in accumulative back extrusion processing of AZ31 magnesium alloy
复制标题
DOI：
10.1016/j.jallcom.2010.07.157
复制
发表时间：
2010-09
影响因子：
6.2
通讯作者：
S. M. Fatemi-Varzaneh;A. Zarei‐Hanzaki;M. Naderi;Ali A. Roostaei
中科院分区：
文献类型：
--
作者：
S. M. Fatemi-Varzaneh;A. Zarei‐Hanzaki;M. Naderi;Ali A. Roostaei
通过剧烈塑性变形（SPD）方法制备的超细晶材料由于其抗拉强度、硬度、韧性、疲劳寿命、光学和电学等性能的提高，在过去的几十年里得到了广泛的研究。变形材料的微观结构和力学性能强烈依赖于SPD过程中实现的应变量和均匀性。累积反挤压法是近年来发展起来的一种制备块体超细结构材料的新技术。了解ABE过程中的应变分布和变形行为有助于更好地理解整个过程。因此，目前的工作已经进行了检查ABE过程中的应变分布和变形行为，通过应用三维有限元模拟与Abaqus/显式的不同阶段的变形。为了验证模拟结果，采用网格法评估。结果表明，一次ABE后，获得了4-5的均匀等效塑性应变。此外，计算结果还表明，法向应变的分布是不均匀的。显微组织观察表明，在ABE循环完成后，具有适当的结构均匀性。
The ultra-fine grained materials produced by severe plastic deformation (SPD) methods have been widely investigated in the last decades due to the enhanced material properties such as improved tensile strength, hardness, toughness, fatigue life, and the optical and electrical related properties. The microstructure and mechanical properties of the deformed materials are strongly dependent on the amount and the homogeneity of strain achieved during the SPD processes. Accumulative back extrusion (ABE) method is a novel severe plastic deformation (SPD) technique which has been recently developed for fabrication of bulk ultra-fine structured materials. The knowledge of strain distribution and deformation behavior during ABE processing may assist the better understanding of the whole process. Therefore the present work has been conducted to examine the strain distribution and deformation behavior during ABE process through applying 3D finite element simulations with Abaqus/Explicit for different stages of deformation. In order to validate the simulation results, a grid method assessment was employed. The results demonstrated that a homogenous equivalent plastic strain of 4–5 has been gained after applying one pass ABE. In addition the results indicate that the distribution of normal strain is inhomogeneous. The microstructural observations have revealed a proper structural homogeneity after completion of an ABE cycle.