(1. 南昌航空大学，轻合金加工科学与技术国防重点学科实验室，南昌 330063; 2. 江西洪都航空工业股份有限公司，南昌 330024)
摘 要: 采用旋转摩擦挤压法制备CNTs/2024Al复合材料，并利用电子背散射衍射技术对复合材料的晶体取向、晶粒尺寸、取向差分布和织构进行分析。结果表明：铝基材的组织为粗大的板条状，其平均晶粒尺寸为48.67 μm，大角度晶界含量为24.4%；经RFE加工后，铝基材变为动态再结晶后的细小等轴晶，平均晶粒尺寸减小为3.22 μm，大角度晶界含量增加至63.9%。当CNTs含量增加至5%时，CNTs/2024Al复合材料平均晶粒尺寸减小至1.97 μm，大角度晶界含量增加至82.7%，CNTs的加入阻止复合材料的晶粒长大。经RFE加工后，铝基材的最大极密度由10.8降低为4.18，轧制织构强度减弱；CNTs的加入对复合材料的织构强度具有弱化作用。
关键字: 旋转摩擦挤压法；CNTs/2024Al复合材料；显微组织；大角度晶界含量；织构
（1. National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology, Nanchang Hongkong University, Nanchang 330063, China; 2. Jiangxi Hongdu Aviation Industry Co., Ltd., Nanchang 330024, China）
Abstract:The carbon nanotubes (CNTs) reinforced 2024 Al matrix composites were fabricated by rotational friction extrusion (RFE).The crystal orientation, grain sizes, misorientation angle distributions and texture were analyzed by electron back scatter diffraction. The results show that the microstructure of aluminum matrix is the coarse strip, the average grain size is 48.67 μm and the large angle grain boundary content is 24.4%. After RFE, the microstructure of aluminum matrix becomes the fine equiaxed crystals by dynamic recrystallization. The average grain size of the RFE aluminum matrix decreases to 3.22 μm, and the large angle grain boundaries increases to 63.9%. With the increase of CNTs content, the average grain size of the CNTs/2024Al composites is gradually reduced to 1.97 μm and the ratio of large angle grain boundaries increases to 82.7% when the content of CNTs increases to 5%. CNTs can prevent the growth of the grains in the composites. The maximum pole density of aluminum matrix decreases from 10.8 to 4.18 and the rolling texture intensity decreases. The recrystallization textures of the composites are weakened by the addition of CNTs.
Key words: rotational friction extrusion; CNTs/2024Al composite; grain size; high angle grain boundary fraction; texture
