The Study On Ignition-Proof Behavior And Strengthing Mechanism Of Magnesium Alloy

Many kinds of magnesium alloys were prepared by casting technique. The microstructure of magnesium alloy and the high temperature oxidation behavior of magnesium alloy were studied by the means of scanning electron microscope (SEM), optical microscopy, X-ray diffraction (XRD) in this paper.The ignition point was increased about sixty degree Centigrade when 1% content of Ce was added into AZ91D.The oxidation film was composed of Ce₂O₃,Al₂O₃ and MgO after XRD and detection SEM analysis.The superficial coat was composed of MgO and the interface layer composed Ce₂O₃ and Al₂O₃ which were compace enough to impede the entrance of oxygen.The phase of CeSb was found when Sb was added into the magnesium-rare earth,it reduced the appearance of large,clavate phase-Al₁₁Ce₃ and it can be used as nucleating center,thus refine crystal grain.The heat-stable phase-Al₂Y was found when Y was added into the magnesium-rare earth.,it can also be used as nucleating center of Mg₁₇Al₁₂ to refine as-cast structure.The ignition point was reduced with the appearance of CeSb when Sb was added into the magnesium-rare earth.The subsequent proof test testified it.