Refinement of Mg2Si reinforcement in a commercial Al–20%Mg2Si in-situ composite with bismuth, antimony and strontium
Refinement of Mg2Si reinforcement in a commercial Al–20%Mg2Si in-situ composite with bismuth, antimony and strontium
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DOI：
10.1016/j.matchar.2013.10.007
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发表时间：
2013-12
影响因子：
4.7
通讯作者：
N. Nordin;Saeed Farahany;A. Ourdjini;T. A. Bakar;E. Hamzah
中科院分区：
文献类型：
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作者：
N. Nordin;Saeed Farahany;A. Ourdjini;T. A. Bakar;E. Hamzah
添加元素对Al-Mg2Si合金进行细化处理，可以改变初生相的形态。本文通过计算机辅助冷却曲线热分析和显微组织检验，研究了铋、锑、锶对Al-20%Mg_2Si自生复合材料特征参数的影响。尺寸、密度和长径比测量表明，添加0.4wt.%的铋、0.8%的Sb和0.01%.1wt.%的锶细化了镁硅增强体。然而，超过这些浓度会导致镁硅颗粒的粗化，而形貌没有变化。结果还表明，添加元素降低了镁硅颗粒的形核和生长温度。铋、锑和锶的细化作用可能与复合熔体中的氧化物双线作为镁硅颗粒的有利形核衬底有关。
Refinement by addition elements of Al–Mg2Si alloys is known to result in a change of primary Mg2Si morphology. In this paper, the effects of Bi, Sb and Sr on the characteristic parameters of Al–20%Mg2Si in-situ composite have been investigated by computer aided cooling curve thermal analysis and microstructural inspection. Size, density and aspect ratio measurements showed that additions of 0.4 wt.% Bi, 0.8 wt.% Sb and 0.01 wt.% Sr refined the Mg2Si reinforcement. Exceeding these concentrations, however, resulted in coarsening of Mg2Si particles with no change in the morphology. The results also showed that addition elements caused a decrease in the nucleation and growth temperatures of Mg2Si particles. The refining effect of Bi, Sb and Sr is likely to be related to the effect of oxide bifilms suspended in the composite melt as favored nucleation substrates for Mg2Si particles.