中文摘要：

研究室温多向锻造过程中锻造道次对高纯铝组织演变的影响,探讨多向锻造大塑性变形过程中高纯铝的变形组织均匀性与再结晶晶粒细化极限.结果表明：当锻造道次达到6次时,开始在试样心部形成一个X形的细晶区,随锻造道次的增加X细晶区不断扩大,直至锻造道次增加至24次,仍无法消除试样中粗晶区与细晶区存在的组织差异.随着锻造道次的增加,细晶区再结晶晶粒先减小再趋于一个极限值,当锻造道次为12时,心部再结晶晶粒尺寸最小约为110μm,随着锻造道次持续增加到24次,心部再结晶晶粒未能进一步细化.

英文摘要：

The effect of forging passes on the refinement of high purity aluminum during multi-forging was investigated. The attention was focused on the structure uniformity due to deformation uniformity and the grain refinement limitation with very high strains. The results show that the fine grain zone in the center of sample expands gradually with the increase of forging passes. When the forging passes reach 6, an X-shape fine grain zone is initially formed. With a further increase of the passes, this X-shape zone tends to spread the whole sample. Limitation in the structural refinement is observed with increasing strains during multi-forging process at the room temperature. The grains size in the center is refined to a certain size （110 μm as forging passes reach 12, and there is no further grain refinement in the center with increasing the forging passes to 24. However, the size of the coarse grains near the surface is continuously decreased with increasing the forging passes to 24.