Internal friction combined with SEM, DSC and XRD measurements was first applied so far to investigate phase transformation behaviors of Fe-Al elemental powders. Special attentions are concentrated on the influence of mechanical ball-milling on microstructure transition during sintering process. A tailored solid solution degree of the Fe-Al powder mixture can be obtained by mechanical ball-milling for different time. Four typical internal friction peaks are observed as termed P₁, P₂, P₃ and P₄ peak respectively for Fe-Al ball-milled powder compact. While for no ball-milled one, only P₂ and P₄ peaks appear. It was rationalized that the four internal friction peaks are probably associated with the formation of FeAl₃, Fe₂Al₅, FeAl₂ and FeAl respectively because of solid diffusion reaction during sintering process. In addition, increasing ball-milling time results in enhancement of solid solution degree owing to refined powder particle and substructure as well as increased solid defect density and interfacial area, and thus phase transformation and corresponding internal friction peaks shift to a lower temperature. The absence of two internal friction peaks in no ball-milled one is ascribed to lower solid solution degree.

迄今为止，首次将内摩擦与SEM，DSC和XRD测量相结合，以研究Fe-Al元素粉末的相变行为。特别注意的是机械球磨对烧结过程中微观结构转变的影响。可以通过在不同时间进行机械球磨获得定制的Fe-Al粉末混合物固溶度。对于Fe-Al球磨粉末压块，观察到四个典型的内部摩擦峰，分别称为P ₁，P ₂，P ₃和P ₄峰。对于没有球磨的球，只有P ₂和P ₄出现峰值。有理由认为，由于烧结过程中的固相扩散反应，四个内部摩擦峰可能分别与FeAl ₃，Fe ₂ Al ₅，FeAl ₂和FeAl的形成有关。另外，由于细化的粉末颗粒和子结构以及增加的固体缺陷密度和界面面积，增加球磨时间导致固溶度的提高，因此相变和相应的内部摩擦峰移至较低的温度。在没有球磨机的情况下，没有两个内部摩擦峰可归因于较低的固溶度。