【摘要】 对MgGdYMn和MgGdYMnSc合金挤压成形,并对挤压合金热处理后的试样进行室温和高温拉伸实验。用金相显微镜(OM)、扫描(SEM)和透射电镜(TEM)等方法,研究添加Mn、Sc元素对该合金组织与力学性能的影响。结果表明:添加Mn元素能有效地提高Mg-9Gd-4Y合金形变细化晶粒的能力以及T6处理提高室温综合性能。添加Sc元素能提高合金的室温伸长率,但强度有所降低。添加Mn的合金在300℃拉伸时强度为200MPa,在400℃拉伸时显示出超塑性行为,而再添加Sc的合金在300℃拉伸时有超塑性表现。同时添加Mn和Sc的合金室温和高温强度下降。更多还原

【Abstract】 Extrusion deformation of MgGdYMn and MgGdYMnSc alloys was carried out firstly,and then the room temperature and high temperature tensile testings of the extruded alloys after heat treatment were performed.Effect of Mn and Sc on microstructure and mechanical properties of the alloys was investigated using optical microscope,scanning electron microscopy and transmission electron microscopy.The results show that the ability of grain refining by deformation and that of increasing integrative properties by T6 treatment of the Mg-9Gd-4Y alloy at high temperature are improved by alloying with element Mn.Plasticity of Mg-9Gd-4Y-0.65Mn alloy at room temperature can be improved by addition of Sc with decreasing strength of the alloy slightly.The ultimate tensile strength of GY94Mn alloy reaches 200MPa at 300℃ and super-plasticity behavior of the GY94MnSc alloy is observed for tensile testing at 400℃.The new alloy of GY94MnSc exhibits super-plasticity behavior for tensile testing at 300℃.GY94MnSc alloy shows decreasing of the strength at room and high temperatures.更多还原