Thermal stable intermetallic particles are important for the heat resistance of magnesium(Mg)alloys.In this work,many lath-like particles formed in α-Mg grains of a Mg-8Gd-3Sm-0.7Al casting alloy when heat-treated at...Thermal stable intermetallic particles are important for the heat resistance of magnesium(Mg)alloys.In this work,many lath-like particles formed in α-Mg grains of a Mg-8Gd-3Sm-0.7Al casting alloy when heat-treated at 873 K.Atomic-resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM) characterizations indicate that most of them are Mg-containing Al_(2)(Gd,Sm),with the atomic ratio of Mg:Al:(Gd,Sm) being ~1:1:1;a small part of them with relatively wider thickness are long-period stacking ordered(LPSO) phases simultaneously containing both 14H and 18R structures.Both followed common orientation relationships with Mg matrix as those reported in previous work.In addition,many Mg laths were observed in the primary blocky Al_(2)(Gd,Sm) phase at grain boundaries,where the atomic ratio of Al:(Gd,Sm) in the Al_(2)(Gd,Sm) matrix was 2:1.Finally,density functional theory(DFT) calculations illustrated the detail structure of the re-constructed Mg/Al_(2)RE interface and simultaneously deduced the underlying reason for the re-dissolution of the newly formed Mg-containing Al_(2)(Gd,Sm) plates in α-Mg matrix.展开更多
基金financially supported by the Scientific and Technological Developing Scheme of Jilin Province(Nos.YDZJ202301ZYTS538 and 20220101239JC)the Chinese Academy of Sciences Youth Innovation Promotion Association (No.2023234)+3 种基金the National Natural Science Foundation of China (No.U21A20323)the Scientific and Technological Developing Scheme of Jilin Province (No.SKL202302038)the Major Scientific and Technological Projects of Hebei Province (No.23291001Z)the Scientific and Technology Project of Hanjiang District。
文摘Thermal stable intermetallic particles are important for the heat resistance of magnesium(Mg)alloys.In this work,many lath-like particles formed in α-Mg grains of a Mg-8Gd-3Sm-0.7Al casting alloy when heat-treated at 873 K.Atomic-resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM) characterizations indicate that most of them are Mg-containing Al_(2)(Gd,Sm),with the atomic ratio of Mg:Al:(Gd,Sm) being ~1:1:1;a small part of them with relatively wider thickness are long-period stacking ordered(LPSO) phases simultaneously containing both 14H and 18R structures.Both followed common orientation relationships with Mg matrix as those reported in previous work.In addition,many Mg laths were observed in the primary blocky Al_(2)(Gd,Sm) phase at grain boundaries,where the atomic ratio of Al:(Gd,Sm) in the Al_(2)(Gd,Sm) matrix was 2:1.Finally,density functional theory(DFT) calculations illustrated the detail structure of the re-constructed Mg/Al_(2)RE interface and simultaneously deduced the underlying reason for the re-dissolution of the newly formed Mg-containing Al_(2)(Gd,Sm) plates in α-Mg matrix.
