(1. 北京科技大学 新金属材料国家重点实验室，北京 100083;
2. 北京有色金属研究总院，北京 100088)
摘 要: 利用液氮球磨、真空热压和挤压工艺制备块体纳米晶Al-Zn-Mg-Cu合金，并对其固溶和时效处理进行研究，得到时效硬度曲线。利用X射线衍射仪和透射电镜对该合金热处理前后的微观组织进行分析，结果表明：块体制备过程中析出的MgZn2可以通过固溶处理使其回溶并在时效后沉淀析出；热压后晶粒尺寸为50~100 nm，热处理后晶粒长大到100 nm，部分晶粒达到200 nm。
关键字: 铝合金；块体纳米晶；低温球磨；固溶处理；时效处理；微观组织
（1. State Key Laboratory for Advanced Metals and Materials,University of Science and Technology Beijing, Beijing 100083, China;
2. Beijing General Research Institute for Nonferrous Metals,Beijing 100088, China）
Abstract:Bulk nanocrystalline Al-Zn-Mg-Cu alloy was fabricated by cryomilling combined with vacuum hot pressing and extrusion. The aging-curve was obtained. The crystal structures and microstructures before and after heat treatment were investigated by X-ray diffractometry (XRD) and transmission electron microscopy(TEM), respectively. The results show that the deposition(MgZn2) of consolidation can be dissolved again by solid-solution, and precipitated during aging. The grain sizes of the bulk nanocrystalline Al-Zn-Mg-Cu alloy produced by vacuum hot pressing are 50−100 nm, some of them grow to 100 nm even part of them reach 200 nm after heat-treatment.
Key words: aluminum alloy; bulk nanocrystalline; cryomilling; solid-solution; aging; microstructure
