摘要
The current work deals with the precipitation behaviors and mechanical properties of the high zinc content of the Mg-Zn-Cu system alloys using gravity casting.Differential scanning calorimetry(DSC)was conducted to describe the solidification process and precipitation behaviors.Thermodynamic calculations were carried out to determine the precipitation conditions using the Thermo-calc software.The microstructures were characterized by an optical microscope(OM),scanning electron microscope(SEM),electron probe micro analysis(EPMA),transmission electron microscopy(TEM),and confocal laser scanning microscope(CLSM).Tensile tests and micro-hardness tests were applied to investigate the mechanical properties.The results substantiated that the Mg Zn Cu phase precipitates in Cu-containing alloys and that the precipitate content,as well as the precipitate temperature,increased with the Cu content from 0 to 3 wt.%according to the thermodynamic calculations and the DSC results.The measured micro-hardness of the alloy was 53.2,57.9,55.8,and 52.5 VHN,respectively.The ultimate tensile strength(UTS),yield strength(YS),and elongation(EL)revealed a λ-like trend of the alloys,and Mg-7Zn-1Cu alloy exhibits the optimum tensile properties with the UTS of 258.9 MPa,YS of 126.2 MPa,and the EL of 14.2%.
基金
financial support from the National key research and development program(2021YFB3702005)
National Natural Science Foundation of China(51974155)
Major Science and Technology Projects of Liaoning Province(2020JH1/10100001)
Outstanding Young Scientific and Technological Talents Project of University of Science and Technology Liaoning(2023YQ07)
the High-level innovation team of Liaoning Province(XLYC1908006)。
