制备方法对AlTiCRE中间合金的组织及细化性能的影响

Effect of Preparation Method on Microstructure and Refining Performance of AlTiCRE Master Alloy

应用自蔓延反应合成法及熔铸搅拌法成功地制备出新型AlTiCRE复合细化剂 ,采用X射线衍射 (XRD)、扫描电镜 (SEM )等对中间合金细化剂相组成及显微组织进行了综合分析。试验结果表明 :两种方法制备的稀土复合细化剂都能细化纯铝晶粒组织 ,反应法制备的细化剂的细化效果明显优于搅拌法细化剂。分析了细化剂中各相在Al液中的形核作用 。

Two new type AlTiCRE master alloys have been prepared with high temperature self-propagating synthesis and molten-stirring method; respectively. The phases and microstructure were investigated by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The synthesizing mechanism of TiC during the preparing process was analyzed. Refining experimental results indicated that two type AlTiCRE refiner could effectively refine the grains in pure aluminum, the former refining effects shows obvious advantage over the latter. This paper also analyzed the refining mechanism of the new type grain refiner. According to the analysis on function nucleus formation of phases of AlTiCRE refiner during the condensation of Aluminum liquid , the multi-lever nucleation mechanism of pure Al was proposed.