论文部分内容阅读
本文讨论铝合金在等通道挤压过程中的晶粒细化机制.发生的晶粒细化主要通过三种机制完成:1)取向分裂诱发形变带;2)应变集中产生的宏观或微观剪切带;3)高角度晶界随应变增加.形变条件和路径、模具几何及材料参数决定形变组织的演化.亚结构和显微剪切带的取向与模具剪切面一致但在原则上与材料的晶体位错滑移系统无关.形变带的晶体取向倾向接近在路径A下稳定织构的取向.在高应变,由于显微组织的压缩和拉长造成的晶界面积增加成为主要晶粒细化机制.变形至一定应变后,形变进入稳态,晶粒细化不再发生.
In this paper, the grain refinement mechanism of aluminum alloy during isopipe extrusion is discussed.The grain refinement occurred mainly through three mechanisms: 1) orientation-induced strain zone; 2) macroscopic or microscopic shear Band; 3) high angle grain boundaries increase with strain. Deformation conditions and pathways, mold geometry and material parameters determine the evolution of the deformed microstructure. The orientation of the substructures and microstrip shear bands is in line with the shear plane of the mold but is, in principle, Regardless of the crystal dislocation slip system.The deformation orientation of the band is close to that of the stable texture under the path A. At high strain the grain boundary area due to the compression and elongation of the microstructure becomes the predominant grain size Deformation to a certain strain, deformation into steady state, grain refinement does not happen.