Correlation between microstructure and mechanical properties of columnar crystals in the directionally solidified Mg-Gd-Y-Er alloy

作     者：D.R.Fang S.S.Zhao X.P.Lin T.Chai Y.Kuo H.Sun Y.Dong D.R.Fang;S.S.Zhao;X.P.Lin;T.Chai;Y.Kuo;H.Sun;Y.Dong

作者机构：School of Materials Science and EngineeringNortheastern UniversityNo.11Alley 3Wenhua RoadHeping DistrictShenyangChina School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004China 

出 版 物：《Journal of Magnesium and Alloys》 (镁合金学报（英文）)

年 卷 期：2022年第10卷第3期

页      面：806-818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 National Natural Science Foundation of China(Nos.51775099 and 51675092) the Natural Science Foundation of Hebei Province(E2018501032 and E2018501033) 

主　　题：Directional solidification Mg-Gd-Y-Er alloy Hard orientation Mechanical prop 

摘      要：The Mg-4.58Gd-0.45Y-0.01 Er alloys with different volume fractions of columnar crystals in hard orientation(orientation factor ofbasal plane slip system is less than 0.2)were prepared by changing the pulling rate to regulate the crystal growth *** tests were performed on the Mg-4.58Gd-0.45Y-0.01 Er alloy at room temperature,and the structure after deformation was investigated by electron backscatter diffraction(EBSD).Subsequently,the strengthening mechanism of columnar crystals in hard orientation was *** results show if orientation factors ofbasal plane slip system of columnar crystals are all greater than 0.4(soft orientation),the alloy has low yield strength σ_(s)(64 MPa),but great work hardening ability,and ultimate tensile strength σ_(b) and elongationδare 114 MPa and 37.3%,*** orientation factors ofbasal plane slip system of columnar crystals are all less than 0.2(hard orientation),the alloy has high strength(σ_(s),125 MPa),but poor plasticity(δ,6.32%).If thehard orientationand thesoft orientationcolumnar crystals are arranged alternately along the direction perpendicular to the crystal growth,the alloy has both superior strength(σ_(s),102 MPa)and excellent plasticity(δ,22.5%)at room *** improved comprehensive mechanical property can be attributed to two *** the one hand,thehard orientationcolumnar crystals can prevent thesoft orientationcrystals deforming,so the strength is *** the other hand,thehard orientationcolumnar crystals themselves can withstand a certain amount of deformation to retain appropriate plasticity.