锌含量对Mg-Gd-Zn合金铸态组织和力学性能的影响

Effcets of Zn Contents on Microstructures and Properties of Mg-Gd-Zn Alloys

采用光学显微镜、X射线衍射、压缩及硬度试验,研究了不同Zn含量对Mg98-xGd2Znx(x=0,0.5,1.0,1.5)合金铸态组织和力学性能的影响。结果表明,当x=0时,Mg98Gd2合金由α-Mg和Mg3Gd相组成;当x=0.5时,Mg97.5Gd2Zn0.5合金由α-Mg和(Mg,Zn)3Gd相组成;当x=1.0和1.5时,合金的组织除了有α-Mg和(Mg,Zn)3Gd相,还出现X相。随着Zn含量的增加,合金的强度和硬度基本都呈先升高后降低的趋势;当Zn含量为1.0%时,合金的抗压强度及屈服强度达到最大值,分别为281.3 MPa和127 MPa,硬度为76.6 HV。

The effects of Zn contents on the microstructures and mechanical properties of Mg98-s,Gd2Znx（x=0,0.5,1.0,1.5） alloys were investigated by optical microscope （OM）, X-ray diffraction（XRD）, hardness testing and compressive testing. The results show that, when x=0, the microstructures of MggsGd2 alloys are composed of Mg3Gd phase and α-Mg phase; when x=0.5, the microstructures of Mg97.5Gd2Zn0.5 alloys are composed of （Mg,Zn）3Gd phase and α-Mg phase; when x=1 and 1.5, the microstructures of alloys are composed of （Mg,Zn）3Gd phase, α-Mg phase and X phase. With the increase of the content of Zn, the rickets hardness and tensile strength increases at first, then decreases. When the Zn content is 1.0% at.%, the vickers hardness, yield strength and compressive strength of the alloys is up to the maximum value, it is 76.6 Hv, 127 MPa, 281.3 MPa, respectively.