中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 22 No. 8 August 2012 |
（1. College of Materials Science and Engineering, Chongqing University, Chongqing 400044, China;
2. Department of Materials Science and Engineering, Norwegian University of Science and Technology,
NO-7491, Trondheim, Norway;
3. Institut de Chimie et des Matériaux Paris-Est, UMR 7182 CNRS-Unversité Paris Val de Marne,
2-8 rue Henri Dunant, 94320, Thiais, France;
4. Hydro Aluminium Research and Technology Development, N-6601 Sunndalsøra,
Norway Montupet SA, 60181 Nogent sur Oise Cedex, France;
5. Mentupet SA, 60181 Nogent sur Oise Cedex, France）
Abstract:The precipitation behaviours of Al3Zr precipitate in the Al-Cu-Zr and Al-Cu-Zr-Ti-V alloys were studied by transmission electron microscopy. Metastable Al3Zr precipitates are homogeneously nucleated in dendrite centres resulting in homogeneous distribution. However, the precipitation in the interdendritic regions is complex and the precipitation morphologies, helical-like and stripe-like shapes, were observed, which are composed of many spherical Al3Zr precipitates. The stripe-like precipitate clusters have preferential orientations along with the á100ñ Al directions, which is inferred to be related to θ′(Al2Cu) and θ phases. Addition of Cu can accelerate the L12→D023 structural transformation of the Al3Zr precipitate.
Key words: aluminium alloys; Al3Zr precipitate; phase transformation
