The effects of a low-voltage pulsed magnetic field on the solidified structure and mechanical properties of DC casting AZ80 magnesium alloy were investigated.The results showed that the solidified structure of the DC ...The effects of a low-voltage pulsed magnetic field on the solidified structure and mechanical properties of DC casting AZ80 magnesium alloy were investigated.The results showed that the solidified structure of the DC casting AZ80 magnesium alloy was refined obviously by the low-voltage pulsed magnetic field and significant grain refinement in the DC casting ingot of AZ80 magnesium alloy was achieved.Meanwhile,the morphology of the dentritic in the DC casting ingot was transformed from coarse dentritic to fine rosette with the application of low-voltage pulsed magnetic field.The ability of deformation of the ingot was enhanced and especially the plasticity of the ingot center after upsetting was improved greatly by more than 80%after deformation.展开更多
To understand the solidification pathway and microstructure evolution of Mg-9Al-2Ca alloy,the cooling curve of the alloy solidified under furnace cooling was measured and the water-quenched samples were observed.The e...To understand the solidification pathway and microstructure evolution of Mg-9Al-2Ca alloy,the cooling curve of the alloy solidified under furnace cooling was measured and the water-quenched samples were observed.The experimental results show that the matrix phase of α-Mg dendrites is first generated at 596℃ during the solidification process,then the eutectic phases of Al_(2)Ca and Mg_(17)Al_(12) are formed at 518 and 447℃,respectively,and the solidification is terminated at 436℃.In the process of solidification,the seaweed dendrites of α-Mg get coarser and are gradually transformed into the global dendrites;besides,the secondary dendrite arms spacing(SDAS)of α-Mg as well as the solid fraction are both increased,while the increasing rate of SDAS of α-Mg and the solid fraction in the temperature region of 600-550℃ is faster than that in the temperature region of 550-436℃.And a power function relationship can be used to illustrate the change of the SDAS and the solid fraction with the temperature of solidification.展开更多
基金Project(51034012)supported by the the National Natural Science Foundation of ChinaProject(2013CB632205)supported by the National Basic Research Program of China
文摘The effects of a low-voltage pulsed magnetic field on the solidified structure and mechanical properties of DC casting AZ80 magnesium alloy were investigated.The results showed that the solidified structure of the DC casting AZ80 magnesium alloy was refined obviously by the low-voltage pulsed magnetic field and significant grain refinement in the DC casting ingot of AZ80 magnesium alloy was achieved.Meanwhile,the morphology of the dentritic in the DC casting ingot was transformed from coarse dentritic to fine rosette with the application of low-voltage pulsed magnetic field.The ability of deformation of the ingot was enhanced and especially the plasticity of the ingot center after upsetting was improved greatly by more than 80%after deformation.
基金Funded by the Ph D Research Startup Foundation of Jining University(No.2017BSZX02)。
文摘To understand the solidification pathway and microstructure evolution of Mg-9Al-2Ca alloy,the cooling curve of the alloy solidified under furnace cooling was measured and the water-quenched samples were observed.The experimental results show that the matrix phase of α-Mg dendrites is first generated at 596℃ during the solidification process,then the eutectic phases of Al_(2)Ca and Mg_(17)Al_(12) are formed at 518 and 447℃,respectively,and the solidification is terminated at 436℃.In the process of solidification,the seaweed dendrites of α-Mg get coarser and are gradually transformed into the global dendrites;besides,the secondary dendrite arms spacing(SDAS)of α-Mg as well as the solid fraction are both increased,while the increasing rate of SDAS of α-Mg and the solid fraction in the temperature region of 600-550℃ is faster than that in the temperature region of 550-436℃.And a power function relationship can be used to illustrate the change of the SDAS and the solid fraction with the temperature of solidification.
