稀土La对半固态A356铝合金凝固组织的影响.pdfVIP

学兔兔 Ju1．2010 · 708· VoI．59 NO．7 稀土La对半固态A356铝合金凝固组织的影响 刘小梅 ，刘 岚 ，刘 政 (1．江西理工大学机电工程学院，江西赣州341000；2．赣州第四中学，江西赣州341000) 摘要：利用A1．La中间合金对A356~~合金进行了细化处理，并用低过热度浇注技术制备了半固态A356~合金浆料，研 究了细化处理对半固态A356~合金初生o【相形貌和尺寸的影响。研究结果表明，细化处理的A356~合金经低过热度浇 注可制备具有颗粒状和蔷薇状初生Q相的半固态浆料，稀土La可显著改善半固态A356~合金中初生or．相的晶粒尺寸和颗 粒形貌。探讨了稀土La对半固态A356~合金初生理相的细化机理。 关键词：半固态；稀土La；A356铝合金；低过热度浇注 中图分类号：TGI46；TG244 文献标识码：A 文章编号：1001—4977(2010)07—0708—04 Effect Of RE on SOIidifiCatiOn Microstructure in Semi．Solid A356 AlUminUm Alloy LIU Xiao—mei’，LIU Lan ，LIU Zheng’ (1。Faculty of Mechanical and Electronical Engineering，Jiangxi University of Science and Technology，Ganzhou 341 000，Jiangxi，China；2．Ganzhou No．4 Higher Middle School， Ganzhou 341 000，Jiangxi，China) Abstract：The semi—solid slurry of A356 aluminum alloy．which was grain·refined by AI—La master alloy，was manufactured by low superheat pouring．The effects of grain-refinement on the morphology and the grain size of the primary oc phase in semi-solid A356 AI alloy were researched． The results indicate that semi-solid A356 AI alloy with particle-like and roseRe—like primary phases can be prepared by low superheat pouring of liquid A356 alloy after grain-refined．The grain size and morphology of primary o(phase in the semi-solid A356 are markedly improved by La．The refining mechanism of La on the grain size of the primary a phase in semi-solid A356 AI alloy was discussed． Key words：semi-solid；r