Al-Si-Fe-Cu-Mg-Ni合金中复合Fe-Si相的研究

Study of the Complex Fe-Si Phase in the Al-Si-Cu-Mg-Ni Alloys

利用透射电镜(TEM)、电子探针(EPMA)等手段研究了Al-Si-Fe-Cu-Mg-Ni合金中复合Fe-Si相的形貌及Fe-Si相对合金高温强度的影响。结果表明:在多元Al-Si-Fe-Cu-Mg-Ni合金中,铁相球化处理后形成块状铁相,且块状铁相与初晶硅相紧密结合,形成复合Fe-Si相。Fe相与初晶硅的连接有明显过渡,过渡层中Si相的晶体结构与FeSi相类似,均为简单立方结构,且(121)FeSi//(010)Si。强度实验还发现Fe相的形态对合金的高温强度有很大的影响,其中针片状Fe相对合金高温强度的提高最小,而复合Fe-Si相对合金高温强度的提高幅度最大,多元Al-Si合金在350℃下的高温强度可达106.05MPa。

The complex Fe-Si phase in the Al-Si-Cu-Fe-Mg-Ni alloy has been studied in this paper. It was found that the addition of Fe with some additive can form block-like Fe phase in Al-Si-Cu-Fe-Mg-Ni alloy, and the phase Fe combined with the primary Si comes into being complex Fe-Si phase. According to EPMA analyzes the phase Fe is AIFeSiMn multiple phase, and there is obviously transition between the phase Fe and primary Si, especially the elements AI, Si, Mn, Fe. The experiment results also show that there is certain electron diffraction connection between the phase FeSi and the phase Si, that is （12^-1）FeSi// （010）Si. In addition, high temperature strength test shows that the morphologies of the phase Fe have great effect on the high temperature strength of the Al-Si based alloys, and compared with flake morphology and fishbone-like, the complex Fe-Si phase has the greater influence on the improvement of the based alloys, and the strength of the multiple Al-Si-Cu-Fe-Mg-Ni alloy at 350 ℃ can reach to 106.05 MPa.