Individual and combined addition of Ti and Ce on the recycled Al-Si-Cu-Fe-Mn alloy was conducted. The microstructures and tensile properties of these fabricated alloys were investigated. In the case of Ti or Ce which was individually added, the added amount was ranging from 0.03 wt.% to 0.09 wt.%. The combined addition of Ti and Ce was set at the ratios of 1 : 1, 1 : 3, and 3 : 1 with a total amount of 0.12 wt.%. Microstructures and phases of these alloys were investigated by using an optical microscope, X-ray diffraction testing, and SEM coupled with EDS. The morphologies of these alloys were quantified by analyzing the SDAS value, length of secondary phases, and phases' distribution uniformity. Tensile testing was carried out for understanding the strengthen effect of the modification process. Results show that the addition of Ce was favorable to the strength and % elongation because the coarse needle-like phase and the polyhedral phase were effectively refined. Their SDAS values and distribution factor were remarkably declined with the increase of the Ce level. The Ti addition could also refine the secondary phases and SDAS values. But its effect was not as prominent as the addition of Ce. Combined addition of Ti and Ce elements at the ratio of 1 : 3 resulted in the samples reaching maximum comprehensive tensile properties. In this case, the short needle-like phase was uniformly distributed in the microstructure. Few polyhedral phases could be found in the Al-Si-Cu-Fe-Mn matrix. The strengthening of these fabricated materials was due to the grain refinement for α-Al and modification for coarse secondary phases. In addition, distribution uniformity of secondary phases was also changed by their modification effects.

中文翻译：

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钛和铈单独和复合添加的再生铝-硅-铜-铁-锰合金的显微组织和拉伸性能表征

在回收的 Al-Si-Cu-Fe-Mn 合金上单独和组合添加 Ti 和 Ce。研究了这些制造合金的微观结构和拉伸性能。在单独添加Ti或Ce的情况下，添加量在0.03wt.％至0.09wt.％的范围内。Ti和Ce的组合添加被设定为1:1、1:3和3:1的比例，总量为0.12wt.%。通过使用光学显微镜、X 射线衍射测试和 SEM 结合 EDS 研究了这些合金的显微组织和相。这些合金的形态通过分析 SDAS 值、第二相的长度和相的分布均匀性来量化。进行拉伸试验以了解改性过程的强化效果。结果表明，由于粗针状相和多面体相被有效地细化，Ce的添加有利于强度和％伸长率。它们的 SDAS 值和分布因子随着 Ce 水平的增加而显着下降。添加 Ti 还可以细化二次相和 SDAS 值。但其效果不如加入Ce那么突出。Ti和Ce元素以1:3的比例组合添加导致样品达到最大综合拉伸性能。在这种情况下，短针状相在微观结构中均匀分布。在 Al-Si-Cu-Fe-Mn 基体中几乎没有发现多面体相。这些制造材料的强化是由于 α-Al 的晶粒细化和粗第二相的改性。此外，