6016铝合金冷轧显微组织和织构的研究

Study on Microstructure and Texture Variation of 6016 Aluminum Alloy during Cold Rolling

摘要:

本文章采用基于EBSD的取向成像技术和SEM的二次电子像和XRD衍射技术,深入研究了6016铝合金冷轧组织和织构的演变规律和机理。结果表明：随着冷轧道次的增加,晶粒沿轧向方向不断伸长,不同晶粒变形不均匀现象先出现后又逐渐消失,链状排列的二相粒子由于金属塑性流变而不断被压碎；小角度位错界面随着变形量增加而不断增多,中低应变量时与轧向呈约40°角度,大应变量时由于变形而诱变成大角度界面,使变形晶粒发生碎化；冷轧初始阶段晶粒通过整体协调转动而形成较多的变形织构,进一步变形时靠近晶界的区域和晶粒内部某些区域相对原始取向易发生向β取向线的偏转,正是这几种偏转导致宏观上以S织构为首的变形织构不断增多,而Cube织构不断减少。

Abstract:

The microstructure and texture variation rule and mechanism of 6016 aluminum alloy during cold rolling was studied in depth in this article, using the Electron Back-Scatter Diffraction technology (EBSD) combined with SEM and XRD. The results show that: with the increase of cold rolling passes, grains constantly elongate along the rolling direction, and inhomogeneous deformation phenomenon between different grains come first but gradually disappear later, also catenation of second phase particles are crushed by metal plastic flow; with the deformation increases, small angle dislocation interfaces increase, and they have an angle about 40°to the rolling direction from low to medium strains, but some of them are induced to large angle interfaces by large strains, which make the deformation grains occurred fragmentation; in the initial rolling stage, overall coordinate deformation and rotation of grains form some deformation texture, and in further deformation, areas near the grain boundary and interior of grains is easy to rotate from grain’s initial orientation to the β orientation line. It is the two mechanism lead the deformation textures, led by S texture, constantly increase, and the Cube texture constantly decrease.