航空用鋁合金超微結(jié)構(gòu)實驗表征

航空用鋁合金超微結(jié)構(gòu)實驗表征Experimental Characterization of Ultrastructure of Aviation Aluminum Alloys

為了使鋁合金更好的服役于航空領(lǐng)域，就有必要對其微觀結(jié)構(gòu)進行實驗表征，從而可以在鋁合金微觀結(jié)構(gòu)和宏觀性能之間搭建橋梁，最終優(yōu)化鋁合金的綜合性能。本文介紹了航空用2xxx，6xxx和7xxx系鋁合金發(fā)展歷程以及時效析出過程中的微觀結(jié)構(gòu)演變，如Al-Cu合金GP區(qū)、Al-Cu-Mg合金GPB區(qū)等重要物相的結(jié)構(gòu)特征，以及Al-Cu-Mg合金S相析出行為等都已得到了透徹的研究；闡述了透射電鏡、掃描透射電鏡、三維原子探針等技術(shù)的結(jié)合在Al-Cu-Mg-Ag合金Ω相、Al-Mg-Si-Cu合金β"相的晶體結(jié)構(gòu)及界面結(jié)構(gòu)以及鋁合金晶間腐蝕機理等研究上的應(yīng)用；本小組實現(xiàn)了復雜選區(qū)電子衍射譜的快速模擬及標定，并基于會聚束電子衍射實現(xiàn)了對析出相體積分數(shù)的精確測量；最后指出，高分辨透射電鏡原位加熱研究及透射電鏡原位力學測試等新技術(shù)手段的應(yīng)用，對深層次研究鋁合金相變規(guī)律、變形行為具有跨時代意義。

In order to improve the comprehensive performance of aluminium alloys for the aviation application, it is necessary to experimentally characterize the microstructure, and thus to build a bridge between the microstructure and macro-performance of aluminum alloys. This paper introduces the brief developing course of 2xxx, 6xxx and 7xxx aluminum alloys and their microstructure evolution during artificial aging.The structural characteristics of significant phases like GP zones in Al-Cu alloys and GPB zones in Al-Cu-Mg alloys, and the precipitation behavior of S phase in Al-Cu-Mg alloys, etc, are thoroughly studied. The application of Transmission Electron Microscopy, Scanning-Transmission Electron Microscopy, 3-Dimentional Atom Probe in the investigations of structure, morphology, composition, interface structures, intergranular corrosion resistance and so on has been reviewed, especially the Ω phase in Al-Cu-Mg-Ag alloys and β" phase in Al-Mg-Si-Cu alloys. Our group has finished the works such as the simulation and characterization of complex selected area electron diffraction patterns in Al alloys, as well as the measuring of the precipitates' volume fraction with high accuracy which is based on the convergent beam electron diffraction.