挤扭成形对等径角挤扭工艺固结纯铝粉末-包套过程的影响（英文）

发布时间：2018-06-20 04:29

  本文选题：铝粉 + 等径角挤扭　； 参考：《Transactions of Nonferrous Metals Society of China》2015年07期

【摘要】：采用3D有限元模拟、实验研究和理论分析,并在与传统等径角挤压工艺对比基础上,系统研究挤扭成形对等径角挤扭工艺固结纯铝粉末-包套过程的影响。模拟结果表明,在等径角挤扭法固结纯铝粉末-包套过程中,挤扭成形起反向背压作用,螺旋通道所提供的旋转剪切变形和高静水压力可大幅增加材料内部的塑性剪切应变,显著改善变形坯料的变形均匀性。在内角为90°、螺旋角为36.5°的方形截面通道模具上,经200℃下1道次等径角挤扭变形实验,成功将纯铝粉末颗粒固结为近致密的块体材料。有限元模拟与实验结果具有较好的一致性。显微组织观察和硬度测试实验结果表明,等径角挤扭法固结的块体材料晶粒更加细小,孔隙得到有效收缩焊合,组织性能均匀性更好。这是由于在等径角挤扭变形过程中剧烈剪切应变大大增加,同时挤扭成形所起的反向背压作用有效提高了Al原子的自扩散系数。
[Abstract]:By using 3D finite element simulation, experimental study and theoretical analysis, and on the basis of comparing with the traditional equal diameter angle extrusion process, the influence of the process of consolidation of pure aluminum powder and sheath on the process of extrusion and torsion forming by equal diameter angle extrusion and torsion process is systematically studied. The simulation results show that in the process of consolidation of pure aluminum powder by equal path angular extrusion and torsion method, the extrusion and torsion forming plays a reverse back pressure role, and the rotational shear deformation and high hydrostatic pressure provided by the spiral channel can greatly increase the plastic shear strain inside the material. The deformation uniformity of the deformed billet is improved obviously. On the square cross section die with 90 掳internal angle and 36.5 掳spiral angle, the pure aluminum powder particles were successfully consolidated into a compact bulk material by 1 pass of secondary diameter angle extrusion and torsional deformation experiment at 200 鈩，

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