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利用 ５ｋＷ ＣＯ_２激光器对 Ａｌ－５．６ｗｔ％Ｍｎ合金进行表面重熔实验，并对熔池的形貌和微观组织进行了分析研究。实验结果表明；重熔区组织较基体组织大大细化，随着生长速度的增大，重熔区组织由Ａｌ６_Ｍｎ枝晶向α（Ａｌ）＋Ａｌ_６Ｍｎ共晶、α（Ａｌ）胞／枝晶及完全无偏析固溶体转变。熔池中存在的对流和激光扫描过程中工作台运动的不稳定造成了熔池表面波纹状组织和熔池中三维条带状组织的出现。
The surface remelting experiment of Al-5.6wt% Mn alloy with 5kW CO_2 laser was carried out, and the morphology and microstructure of the molten pool were analyzed. The experimental results show that the microstructure of the remelted zone is much refined than that of the matrix. With the increase of the growth rate, the microstructure of the remelted zone changes from Al6_Mn dendrite to α (Al) + Al_6Mn eutectic, α (Al) Unbiased solid solution transformation. The presence of convection in the weld pool and the unstable motion of the stage during the laser scanning caused the appearance of three-dimensional ribbon-like structures in the weld pool and in the weld pool.