【摘要】 研究了锑对AZ91D镁合金微观组织的影响。在AZ91D镁合金熔炼过程中加入三氧化二锑引入锑元素,用光学显微镜对加锑前后合金显微组织及其变化情况进行研究,发现锑的加入可使AZ91D镁合金的组织发生明显变化,β-Mg17Al12脆性相由连续网状分布逐渐变为离散状。同时利用扫描电镜、能谱仪和透射电镜分析了锑在合金中的存在形式。结果表明,锑在AZ91D镁合金中主要以两种形式存在:固溶在α-Mg、β相中;形成新相Mg3Sb2。锑在镁合金中生成的新相Mg3Sb2既作为异质形核核心细化组织,又会聚集在固液界面前沿抑制晶体的长大,从而对镁合金起到细化晶粒的作用。更多还原

【Abstract】 The effect of antimony on the microstructure of AZ91D magnesium alloy has been investigated. In the smelting process of magnesium alloy, Sb2O3 was added as the antimony sources, which could supply fine and active antimony. The experimental results show that the microstructure of AZ91D magnesium alloy is refined effectively due to the addition of antimony. Antimony in AZ91D magnesium alloy is detected in two forms: the solution phase and Mg3Sb2 particle, by the SEM, EDS and TEM. The mechanism of refining the microstructure is also discussed. The analysis indicates that Mg3Sb2 is not only the heterogeneous nucleus of the crystal but also the countercheck of the crystal growth.更多还原