Room temperature compressive properties and strengthening mechanism of Mg96.17Zn3.15Y0.50Zr0.18 alloy solidified under high pressure
来源期刊：Journal of Rare Earths2020年第6期
论文作者：Xiaoping Lin Zhibin Fan Chang Xu Kunyu Guo Chang Xu Shiqi Guo
文章页码：657 - 664
摘 要：The microstructures of Mg96.17Zn3.15Y0.50Zr0.18 alloys solidified under 2-6 GPa high pressure were investigated by employing SEM（EDS） and TEM.The strengthening mechanism of experimental alloy solidified under high pressure is also discussed by analyzing the compressive properties and compression fracture morphology.The results show that the microstructure of experimental alloy becomes significantly fine-grained with increasing GPa level high pressure during solidification process,and the secondary dendrite arm spacing reduces from 40 μm at atmospheric pressure to 10 μm at 6 GPa pressure.The morphology of the second phases changes from the net structure by the lamellar-type eutectic structure at atmospheric pressure to discontinuous thin rods or particles at 6 GPa pressure.Besides,the solid solubility of Zn in the Mg matrix is improved with the increase of the solidification pressure.Compared with atmospheric-pressure solidification,high-pressure solidification can improve the strength of the experimental alloy.The compressive stre ngth is improved from 263 to 437 MPa at 6 GPa.The fracture mechanism of the experimental alloy changes from cleavage fracture at atmospheric pressure to quasi-cleavage fracture at high pressure.The main mechanism of the strength improvement of the experimental alloy includes the grain refinement strengthening caused by the refinement of the solidification microstructure,the second phase strengthening caused by the improvement of the morphology and distribution of the second phases,and solid solution strengthening caused by the increase of the solid solubility of Zn in the Mg matrix.
Xiaoping Lin1,2，Zhibin Fan1，Chang Xu3，Kunyu Guo3，Chang Xu3，Shiqi Guo3
1. School of Materials and Engineering,Northeast University2. State Key Laboratory of Metastable Materials Science and Technology3. School of Resources and Materials,Northeast University at Qinhuangdao
摘 要：The microstructures of Mg96.17Zn3.15Y0.50Zr0.18 alloys solidified under 2-6 GPa high pressure were investigated by employing SEM（EDS） and TEM.The strengthening mechanism of experimental alloy solidified under high pressure is also discussed by analyzing the compressive properties and compression fracture morphology.The results show that the microstructure of experimental alloy becomes significantly fine-grained with increasing GPa level high pressure during solidification process,and the secondary dendrite arm spacing reduces from 40 μm at atmospheric pressure to 10 μm at 6 GPa pressure.The morphology of the second phases changes from the net structure by the lamellar-type eutectic structure at atmospheric pressure to discontinuous thin rods or particles at 6 GPa pressure.Besides,the solid solubility of Zn in the Mg matrix is improved with the increase of the solidification pressure.Compared with atmospheric-pressure solidification,high-pressure solidification can improve the strength of the experimental alloy.The compressive stre ngth is improved from 263 to 437 MPa at 6 GPa.The fracture mechanism of the experimental alloy changes from cleavage fracture at atmospheric pressure to quasi-cleavage fracture at high pressure.The main mechanism of the strength improvement of the experimental alloy includes the grain refinement strengthening caused by the refinement of the solidification microstructure,the second phase strengthening caused by the improvement of the morphology and distribution of the second phases,and solid solution strengthening caused by the increase of the solid solubility of Zn in the Mg matrix.
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