As-cast AM60 magnesium alloy ingot with grains coarser than those of as-extruded AZ series is more liable to produce cracks under ECAD with severe shear strain. A feasible scheme of equal channel angular deformation (...As-cast AM60 magnesium alloy ingot with grains coarser than those of as-extruded AZ series is more liable to produce cracks under ECAD with severe shear strain. A feasible scheme of equal channel angular deformation (ECAD) for as-cast AM60 magnesium alloy ingot was proposed in this paper. The tests were conducted on Instron machine with hydraulic back-force machine. Through analysing load us displacement curves, the effects of ECAD processing conditions on deformability and microstructure of as-cast magnesium AM60 billets were discussed. During testing, the back-force employment was helpful to keep ECAD processing more stable. And with back-force, it was observed that the number of ECAD passes in different routes could tremendously affect the deformability and microstructure of magnesium specimens. It was concluded that ECAD processing is entirely feasible for as-cast magnesium AM60 alloy under severe shear strain, and back-force employment, multi-passes deformation and lubrication of graphite paper are the factors primarily beneficial to improvement of deformability and refinement of grained structure. This work provides a way to produce magnesium alloy with fine-grained structure directly from casting ingot by ECAD technique.展开更多
Editor＇s Note： UN Secretary General Ban Ki-moon visited China on July 6-10, his 10th trip to the country since assuming office on January I, 2007. Known for his unwavering determination to bring nations together, Ba...Editor＇s Note： UN Secretary General Ban Ki-moon visited China on July 6-10, his 10th trip to the country since assuming office on January I, 2007. Known for his unwavering determination to bring nations together, Ban has always taken a hands-on approach to the thorniest issues. His tenure ends this year after leading the UN for a decade. During the Beijing leg of Ban＇s five-day visit, Beijing Review President Li Yafang and reporter Liu Yunyun sat down with the secretary general to talk about his experience and his vision for the world. An edited excerpt of the interview follows：展开更多
基金This work was supported,in part,by the China Scholarship Council under grant number 21852035in part,was supported by the Australia Research Council.
文摘As-cast AM60 magnesium alloy ingot with grains coarser than those of as-extruded AZ series is more liable to produce cracks under ECAD with severe shear strain. A feasible scheme of equal channel angular deformation (ECAD) for as-cast AM60 magnesium alloy ingot was proposed in this paper. The tests were conducted on Instron machine with hydraulic back-force machine. Through analysing load us displacement curves, the effects of ECAD processing conditions on deformability and microstructure of as-cast magnesium AM60 billets were discussed. During testing, the back-force employment was helpful to keep ECAD processing more stable. And with back-force, it was observed that the number of ECAD passes in different routes could tremendously affect the deformability and microstructure of magnesium specimens. It was concluded that ECAD processing is entirely feasible for as-cast magnesium AM60 alloy under severe shear strain, and back-force employment, multi-passes deformation and lubrication of graphite paper are the factors primarily beneficial to improvement of deformability and refinement of grained structure. This work provides a way to produce magnesium alloy with fine-grained structure directly from casting ingot by ECAD technique.
文摘Editor＇s Note： UN Secretary General Ban Ki-moon visited China on July 6-10, his 10th trip to the country since assuming office on January I, 2007. Known for his unwavering determination to bring nations together, Ban has always taken a hands-on approach to the thorniest issues. His tenure ends this year after leading the UN for a decade. During the Beijing leg of Ban＇s five-day visit, Beijing Review President Li Yafang and reporter Liu Yunyun sat down with the secretary general to talk about his experience and his vision for the world. An edited excerpt of the interview follows：
