The influence of trace Y on the microstructure evolution and mechanical properties of Mg_(100−x)Y_(x)(x=0.25,_(0.75),1.5,3,4,5,at.%)alloys during solidification process was investigated via molecular dynamics(MD)simul...The influence of trace Y on the microstructure evolution and mechanical properties of Mg_(100−x)Y_(x)(x=0.25,_(0.75),1.5,3,4,5,at.%)alloys during solidification process was investigated via molecular dynamics(MD)simulations.The results show that the Mg_(100−x)Y_(x) alloys are mainly characterized by a face-centered cubic(FCC)crystal structure;this is different from pure metal Mg,which exhibits a hexagonal close packed(HCP)structure at room temperature.Among these alloys,Mg_(99.25)Y_(0.75) has a larger proportion of FCC cluster structures,with the highest fraction reaching 56.65%.As the content of the Y increases up to 5 at.%(Mg95Y5 alloy),the amount of amorphous structures increases.The mechanical properties of the Mg_(100−x)Y_(x) alloys are closely related to their microstructures.The Mg_(99.25)Y_(0.75) and Mg_(97)Y_(3) alloys exhibit the highest yield strengths of 1.86 and 1.90 GPa,respectively.The deformation mechanism of the Mg−Y alloys is described at the atomic level,and it is found that a difference in the FCC proportion caused by different Y contents leads to distinct deformation mechanisms.展开更多
In the present study,the effect of Zn content on the microstructure and deformation behavior of the as-cast Mg-Zn-Y-Nd alloy has been investigated.The results showed that as Zn content increased,the volume fraction of...In the present study,the effect of Zn content on the microstructure and deformation behavior of the as-cast Mg-Zn-Y-Nd alloy has been investigated.The results showed that as Zn content increased,the volume fraction of secondary phases increased.Moreover,the phase transformation from W-phase to W-phase and I-phase occurred.In the as-cast state,W-phase exists as eutectic and large block form.When Zn content increases to 6 and 8%（wt%）,small I-phase could precipitate around W-phase particles.Additionally,the effect of Zn content on the tensile properties and deformation behavior varies with the testing temperature.At room temperature,the tensile strength increases with Zn content,whereas the elongation increases initially and then decreases.At 250℃,as Zn content increases,the tensile strength decreases initially and then increases slightly,whereas the elongation decreases.At 350℃,the elongation increases with Zn content,whereas the tensile strength decreases initially and then increases slightly.展开更多
基金the National Key Research and Development Program of China (No. 2017YFGX090043)the Program for New Century Excellent Talents in University, China (No. NCET-12-0170) for supporting this work。
文摘The influence of trace Y on the microstructure evolution and mechanical properties of Mg_(100−x)Y_(x)(x=0.25,_(0.75),1.5,3,4,5,at.%)alloys during solidification process was investigated via molecular dynamics(MD)simulations.The results show that the Mg_(100−x)Y_(x) alloys are mainly characterized by a face-centered cubic(FCC)crystal structure;this is different from pure metal Mg,which exhibits a hexagonal close packed(HCP)structure at room temperature.Among these alloys,Mg_(99.25)Y_(0.75) has a larger proportion of FCC cluster structures,with the highest fraction reaching 56.65%.As the content of the Y increases up to 5 at.%(Mg95Y5 alloy),the amount of amorphous structures increases.The mechanical properties of the Mg_(100−x)Y_(x) alloys are closely related to their microstructures.The Mg_(99.25)Y_(0.75) and Mg_(97)Y_(3) alloys exhibit the highest yield strengths of 1.86 and 1.90 GPa,respectively.The deformation mechanism of the Mg−Y alloys is described at the atomic level,and it is found that a difference in the FCC proportion caused by different Y contents leads to distinct deformation mechanisms.
基金supported financially by the Shenzhen Technology Innovation Plan(Nos.CXZZ20140731091722497 and CXZZ20140419114548507)the Shenzhen Basic Research Project(Nos.JCYJ20150529162228734,JCYJ20160407090231002,JCYJ20150625155931806 and JCYJ20160427100211076)The Thirteen Five National Key Research and Development Plan(No.2016YFC1102601)
文摘In the present study,the effect of Zn content on the microstructure and deformation behavior of the as-cast Mg-Zn-Y-Nd alloy has been investigated.The results showed that as Zn content increased,the volume fraction of secondary phases increased.Moreover,the phase transformation from W-phase to W-phase and I-phase occurred.In the as-cast state,W-phase exists as eutectic and large block form.When Zn content increases to 6 and 8%（wt%）,small I-phase could precipitate around W-phase particles.Additionally,the effect of Zn content on the tensile properties and deformation behavior varies with the testing temperature.At room temperature,the tensile strength increases with Zn content,whereas the elongation increases initially and then decreases.At 250℃,as Zn content increases,the tensile strength decreases initially and then increases slightly,whereas the elongation decreases.At 350℃,the elongation increases with Zn content,whereas the tensile strength decreases initially and then increases slightly.
