摘要
Abstract
The effects of the content of Gd on microstructure and mechanical properties of cast Mg-6Al-xGd (x=0,0.6,0.9,1.2,1.5,1.8％,mass fraction) magnesum alloys were investigated using X-ray diffraction analysis,scanning electron microscope,optical microscopy and tensile properties test.The results show that,with the content of Gd increasing gradually,the grain size of α-Mg first decreases and then increases,and the volume and the number of β-Mg17Al12 phase decreases continuously to make the morphology ofβ-Mg17Al12 change from continuous mesh to intermittent mesh,granular.In addition,Al2Gd phases disperse in the microstructure of the alloy.The element of Gd can significantly refine the grain of magnesium alloy,the grain size is the smallest when the content reaches 0.9％.The tensile strength of as-cast Mg-6Al-xGd alloy at room temperature tends to firstly increasing and then decreasing,when the amount of Gd is 0.9％,the tensile strength is 210.93 MPa,which is increased by 21.4％ compared with Mg-6Al alloy.The tensile fracture of the as-cast alloy has a lot of dimples and tear ridges,and the alloy is characterized by the mixed fracture of the ductile and brittle.关键词
Mg-6Al镁合金/稀土Gd/显微组织/力学性能Key words
Mg-6Al alloy/rare earth Gd/microstructure/mechanical properties分类
矿业与冶金
