MnAl-C permanent magnetic alloy has a giant anisotropy (H_a) of 57 kOe; however, it is difficult to synthesize high coercivity MnAl-C permanent magnetic material. In this research work, the microstructure, phase composition, magnetic properties and magnetic domain of different content Cu added (Mn₅₅Al_45−xCu_x)₁₀₀C₂ (x = 0, 1, 2, 3) alloys were systematically investigated. The added Cu could stabilize both the ε and ferromagnetic τ phase when the content of the added Cu is x ＜ 2 in the (Mn₅₅Al_45−xCu_x)₁₀₀C₂ (x = 0, 1, 2, 3) alloy system. The added Cu precipitated, formed a cellular structure shell around each Mn-rich τ phase grain and pin the magnetic domain movement. The added Cu promoted the transformation of the domain structure within the Mn-rich τ phase from narrow slender shape to isoaxial grain shape.

MnAl-C永磁合金具有57 kOe的巨大各向异性（H _a）；然而，难以合成高矫顽力的MnAl-C永磁材料。_{本研究工作对不同含量Cu添加(Mn 55} Al _45−x Cu _x ) ₁₀₀ C ₂ (x = 0, 1, 2, 3)合金的显微组织、相组成、磁性能和磁畴进行了系统研究。_{当(Mn 55} Al _45−x Cu _x ) ₁₀₀ C ₂中添加的Cu含量为x＜2时，添加的Cu可以稳定ε相和铁磁τ相(x = 0, 1, 2, 3) 合金系统。添加的Cu沉淀，在每个富含Mn的τ相晶粒周围形成蜂窝状结构壳，并固定磁畴运动。添加的Cu促进了富含Mn的τ相内的畴结构从窄细长形状向等轴晶粒形状的转变。