Strengthening mechanisms in magnesium alloys containing ternary Ⅰ,W and LPSO phases

作     者：N.Tahreen D.F. Zhang F.S. Pan X.Q. Jiang D.Y. Li D.L. Chen 

作者机构：Department of Mechanical and Industrial Engineering Ryerson University Toronto Ontario MSB 2K3 Canada College of Materials Science and Engineering Chongqing University Chongqing 400045 China National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing 400044 China Advanced Materials Research Center ChongqingAcademy of Science and Technology Chongqing 401123 China Faculty of Materials and Energy Southwest University Chongqing 400715 China Department of Chemical and Materials Engineering University of Alberta Alberta T6G 11-19 Canada 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2018年第34卷第7期

页      面：1110-1118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：the Natural Sciences and Engineering Research Council of Canada (NSERC) Ontario Trillium Scholarships (OTS) program for providing financial support financial support by the Premier’s Research Excellence Award (PREA) Canada Foundation for Innovation (CFI) Ryerson Research Chair (RRC) program the Ministry of Science and Technology of China (2014DFG52810) National Great Theoretic Research Project of China (2013CB632200) National Natural Science Foundation of China (Project 51474043) Ministry of Education of China (SRFDR 20130191110018) Chongqing Municipal Government(CSTC2013JCYJC60001) Chongqing Science and Technology Commission (CSTC2011gjhz50001) 

主　　题：Magnesium alloy I-phase W-phase LPSO phase Strengthening mechanism 

摘      要：This study was aimed at identifying underlying strengthening mechanisms and predicting the yield strength of as-extruded Mg-Zn-Y alloys with varying amounts of yttrium （Y） element. The addition of Y resulted in the formation of ternary 1 （Mg3YZn6）, W （Mg3Y2Zn3） and LPSO （Mg12YZn） phases which subse- quently reinforced alloys ZM31 ＋ 0.3Y, ZM31 ＋ 3.2Y and ZM31 ＋ 6Y, where the value denoted the amount of Y element （in wt%）. Yield strength of the alloys was determined via uniaxial compression testing, and grain size and second-phase particles were characterized using OM and SEM. In-situ high-temperature XRD was performed to determine the coefficient of thermal expansion （CTE）, which was derived to be 1.38 x 10^-5 K^-1 and 2.35 x 10^-5 K^-1 for W and LPSO phases, respectively. The individual strengthening effects in each material were quantified for the first time, including grain refinement, Orowan looping, thermal mismatch, dislocation density, load-bearing, and particle shearing contributions. Grain refinement was one of the major strengthening mechanisms and it was present in all the alloys studied, irrespective of the second-phase particles. Orowan looping and crE mismatch were the predominant strengthening mechanisms in the ZM31＋0.3Y and ZM31 ＋ 3.2Y alloys containing I and W phases, respectively, while load-bearing and second-phase shearing were the salient mechanisms contributing largely to the superior yield strength of the LPSO-reinforced ZM31 ＋ 6Y alloy.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.