文献类型：期刊文献

中文题名：搅拌摩擦加工调控7075铝合金织构演变及强韧化机制研究

英文题名：Stirring Friction Processing Controlling Texture Evolution and Toughening Mechanism of 7075 Aluminum Alloy

作者：邓江流 蒙迅 朱单单 龙绍檑 潘胜善 凌敏

第一作者：邓江流

机构：[1]贵阳职业技术学院,贵阳550081;[2]贵州永红换热冷却技术有限公司,贵州惠水550600;[3]贵州理工学院,贵阳550003

第一机构：贵阳职业技术学院,贵阳550081

年份：2026

卷号：18

期号：1

起止页码：26-35

中文期刊名：精密成形工程

外文期刊名：Journal of Netshape Forming Engineering

收录：;北大核心:【北大核心2023】；

基金：贵州省基础研究计划(自然科学类)(黔科合基础-ZK[2024]一般516);贵州省基础研究计划(自然科学类)项目(黔科合基础[2020]1Y199);高层次人才科研启动经费项目(XJGC20190949)。

语种：中文

中文关键词：搅拌摩擦加工;7075铝合金;晶粒细化;几何必须位错;织构优化;力学性能

外文关键词：friction stir processing(FSP);7075 aluminum alloy;grain refinement;geometrically necessary dislocations(GND);texture optimization;mechanical properties

摘要：目的采用搅拌摩擦加工(FSP)技术对7075铝合金轧板的微观织构进行调控,从而改善其力学性能。方法通过多尺度表征手段(扫描电子显微镜SEM、电子背散射衍射EBSD、透射电子显微镜TEM),系统揭示了工艺、结构与性能之间的关联机制。特别关注了剪切变形与摩擦热的协同作用对铝合金微观组织的影响,以及不同加工参数对织构演变的影响。结果FSP技术能将原始粗大且不均匀的组织(晶粒尺寸约10μm)转变为超细等轴晶结构,在最佳工艺参数(1000 r/min和70 mm/min)下,获得的最小晶粒尺寸为0.66μm。梯度加工强度显著影响位错密度分布,其中几何必须位错(GND)密度在最佳工艺参数下达到峰值249×10^(12)m^(-2)。织构演变显示出显著的参数依赖性,在最佳工艺参数下,硬取向A/E/S织构体积分数显著降低,而软取向C织构{001}<100>的体积分数则明显增加,整体织构强度下降约25%。尽管1000 r/min×70 mm/min加工试样屈服强度因织构强化减弱而降低93 MPa,但由于晶粒细化、高位错密度及软织构取向的协同作用,抗拉强度和延伸率分别达到527 MPa和22%,较母材提升了8.5%和86%。结论揭示了FSP工艺参数对织构演变的影响规律,并阐明了以软取向织构为主导的形变硬化机制。这为攻克高强铝合金强塑性倒置难题提供了新的理论框架和工艺指导。通过微观结构的协同优化,成功实现了7075铝合金强度与塑性的双向提升。
The work aims to regulate the microstructural texture of 7075 aluminum alloy sheets using Friction Stir Processing(FSP)technology to improve its mechanical properties.A multi-scale characterization approach involving scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),and transmission electron microscopy(TEM)was employed to systematically reveal the correlation mechanisms among processing,structure,and performance.The study particularly focused on the synergistic effects of shear deformation and frictional heat on the microstructural evolution of the aluminum alloy,as well as the influence of various processing parameters on texture development.The study found that FSP technology could transform the original coarse and inhomogeneous microstructure(with an average grain size of approximately 10μm)into a refined equiaxed grain structure.Optimal processing parameters(1000 r/min and 70 mm/min)resulted in a minimum grain size of 0.66μm.The gradient processing intensity significantly affected the distribution of dislocation density,with the geometrically necessary dislocation(GND)density reaching a peak value of 249×10^(12)m^(-2)under these parameters.Texture evolution exhibited significant parameter dependence.Under optimal process parameters,the volume fraction of hard-oriented A/E/S textures markedly decreased,while the soft-oriented cube texture{001}<100>showed a significant increase,leading to an overall texture strength reduction of approximately 25%.Although the yield strength of the sample processed at 1000 r/min×70 mm/min decreased by 93 MPa due to reduced texture strengthening,the synergistic effects of grain refinement,high dislocation density,and soft texture orientation contributed to achieving a tensile strength of 527 MPa and an elongation of 22%,representing improvements of 8.5%and 86%compared with the base material,respectively.This study elucidates the influence of FSP processing parameters on texture evolution and clarifies the deformation hardening mechanism dominated by soft orientation textures.It provides a new theoretical framework and process guidance for overcoming the challenge of achieving high strength and plasticity in aluminum alloy.Through the synergistic optimization of the microstructure,a successful bidirectional enhancement of strength and plasticity in 7075 aluminum alloy is achieved.