高强铝合金的时效或形变诱导相变强韧化都与亚稳相（包括纳米晶、准晶或非晶）结构及其演化紧密相关。本研究针对两类代表性高强铝合金，一是商用高强铝锂合金，二是铝基非晶合金，首先研究其在等温时效或形变诱导相变条件下的断裂行为，接下来使用固体核磁共振波谱技术开展铝合金中亚稳相结构及演化的测量，并探讨铝合金强韧化机理。

The structural evolution of metastables (including nanocrystalline, quasicrystalline and amorphous states) is closely related to age- or deformation-induced strenghening and toughening in high-strength Al alloys.In this project, fracture behaviors in response to thermal aging and deformation-induced phase transition will firstly be carried out for two typical high-strength aluminum alloys, one is commercial high-strength Al-Li alloys, the other one is Al based metallic glasses. Solid state nuclear magnetic resonance spectroscopy will then primarily be employed to investigate the structural evolution of metastable phases induced either by isothermal aging or plastic strain in such two types of high-strength Al alloys. Finally, the microscopic strenghening or toughening mechanisms in aluminum alloys will be explored and discussed in general.