Special nanostructures in Al-Mg alloys subjected to high pressure torsion

作     者：刘满平 Hans J.ROVEN 刘新涛 Maxim MURASHKIN Ruslan Z.VALIEV Tamas UNGáR Levente BALOGH 

作者机构：National Engineering Research Center of Light Alloy Net FormingShanghai Jiao Tong University Department of Materials Science and EngineeringNorwegian University of Science and Technology Institute of Physics of Advanced MaterialsUfa State Aviation Technical University Department of Materials PhysicsEtvs University 

出 版 物：《Transactions of Nonferrous Metals Society of China》 (中国有色金属学报（英文版）)

年 卷 期：2010年第20卷第11期

页      面：2051-2056页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：Project(50971087) supported by the National Natural Science Foundation of China Project supported by the Research Council of Norway under the Strategic University Program on Light Metals Technology Projects(67692, 71594) supported by the Hungarian National Science Foundation 

主　　题：aluminum alloys severe plastic deformation high pressure torsion grain boundary structure deformation twinning nanostructures 

摘      要：Deformation twins and stacking faults were observed in nanostructure A1-Mg alloys subjected to high pressure torsion. These observations are surprising because deformation twinnings have never been observed in their coarse-grained counterparts under normal conditions. Experimental evidences are introduced on non-equilibrium grain boundaries, deformation twinnings and partial dislocation emissions from grain boundaries. Some of these features can be explained by the results reported from molecular-dynamics simulations of pure FCC metals. Special emphasis is laid on the recent observations of high density hexagonal and rhombic shaped nanostructures with an average size of 3 nm in the A1-Mg alloys processed by high pressure torsion. A possible formation process of these nanostructures is proposed based on molecular-dynamics simulations.