In recent years,modification of texture distribution has been considered a valid approach to improve the room-temperature(RT)formability of magnesium(Mg)alloys.In this study,a novel Mgsingle bond2Znsingle bond3Lisingl...In recent years,modification of texture distribution has been considered a valid approach to improve the room-temperature(RT)formability of magnesium(Mg)alloys.In this study,a novel Mgsingle bond2Znsingle bond3Lisingle bond1Gd alloy sheet with weak elliptical-texture was fabricated by cold rolling and subsequent annealing,and it showed an excellent Erichsen(IE)value near 7.1 mm.Both quasi-in-situ electron backscatter diffraction(EBSD)and transmission electron microscopy(TEM)analysis indicate that considerable basal and pyramidal dislocations can be activated in the cold rolling process.During annealing,these dislocations can induce nucleation and then cause preferential misorientation relationships around〈uvt0〉concerning the nuclei and parent grains,which can facilitate the formation of elliptical texture.Furthermore,the particle-stimulated nucleation(PSN)mechanism and the co-segregation of Zn and Gd at grain boundaries(GB)further weak texture intensity.Finally,the mechanical properties of the Mgsingle bond2Znsingle bond3Lisingle bond1Gd alloy sheet are significantly improved.展开更多
The microstructure of Mg-8Zn-4Al-1Ca aged alloy was investigated by TEM and HRTEM. The results show that the hardening produced in the Mg-8Zn-4Al-1Ca alloy is considerably higher than that in the Mg-8Zn-4A1 alloy. A d...The microstructure of Mg-8Zn-4Al-1Ca aged alloy was investigated by TEM and HRTEM. The results show that the hardening produced in the Mg-8Zn-4Al-1Ca alloy is considerably higher than that in the Mg-8Zn-4A1 alloy. A dense dispersion of disc-like Ca2Mg6Zn3 precipitates are formed in Mg-8Zn-4Al-1Ca alloy aged at 160 ℃ for 16 h. In addition, the lattice distortions, honeycomb-looking Moir＆#233; fringes, edge dislocations and dislocation loop also exist in the microstructure. The precipitates of alloy aged at 160 ℃ for 48 h are coarse disc-like and fine dispersed grainy. When the alloy is subjected to aging at 160 ℃ for 227 h, the microstructure consists of numerous MgZn2 precipitates and Ca2Mg6Zn3 precipitates. All the analyses show that Ca is a particularly effective trace addition in improving the age-hardening and postponing the formation of MgZn2 precipitates in Mg-8Zn-4Al alloy aged at 160 ℃.展开更多
基金supports from the National Natural Science Foundation of China(51901204,52161023,52271249)Science and Technology project of Yunnan Precious Metal Laboratory(YPML-2023050208)+1 种基金Yunnan Science and Technology Planning Project(202201AU070010,202301AT070276,202302AB080008,202303AA080001)supported by Yunnan Key Laboratory of Electromagnetic Materials and Devices.
文摘In recent years,modification of texture distribution has been considered a valid approach to improve the room-temperature(RT)formability of magnesium(Mg)alloys.In this study,a novel Mgsingle bond2Znsingle bond3Lisingle bond1Gd alloy sheet with weak elliptical-texture was fabricated by cold rolling and subsequent annealing,and it showed an excellent Erichsen(IE)value near 7.1 mm.Both quasi-in-situ electron backscatter diffraction(EBSD)and transmission electron microscopy(TEM)analysis indicate that considerable basal and pyramidal dislocations can be activated in the cold rolling process.During annealing,these dislocations can induce nucleation and then cause preferential misorientation relationships around〈uvt0〉concerning the nuclei and parent grains,which can facilitate the formation of elliptical texture.Furthermore,the particle-stimulated nucleation(PSN)mechanism and the co-segregation of Zn and Gd at grain boundaries(GB)further weak texture intensity.Finally,the mechanical properties of the Mgsingle bond2Znsingle bond3Lisingle bond1Gd alloy sheet are significantly improved.
基金Project(51141007)supported by the National Natural Science Foundation of ChinaProject(E2013501096)supported by Hebei Province Natural Science Foundation,China
文摘The microstructure of Mg-8Zn-4Al-1Ca aged alloy was investigated by TEM and HRTEM. The results show that the hardening produced in the Mg-8Zn-4Al-1Ca alloy is considerably higher than that in the Mg-8Zn-4A1 alloy. A dense dispersion of disc-like Ca2Mg6Zn3 precipitates are formed in Mg-8Zn-4Al-1Ca alloy aged at 160 ℃ for 16 h. In addition, the lattice distortions, honeycomb-looking Moir＆#233; fringes, edge dislocations and dislocation loop also exist in the microstructure. The precipitates of alloy aged at 160 ℃ for 48 h are coarse disc-like and fine dispersed grainy. When the alloy is subjected to aging at 160 ℃ for 227 h, the microstructure consists of numerous MgZn2 precipitates and Ca2Mg6Zn3 precipitates. All the analyses show that Ca is a particularly effective trace addition in improving the age-hardening and postponing the formation of MgZn2 precipitates in Mg-8Zn-4Al alloy aged at 160 ℃.
