中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 30 No. 5 May 2020 |
（1. Light Alloy Research Institute, Central South University, Changsha 410083, China;
2. State Key Laboratory of High Performance and Complex Manufacturing, Central South University, Changsha 410083, China;
3. Kunming Metallurgical Research Institute, Kunming 650031, China;
4. State Key Laboratory of Pressure Hydrometallurgical Technology of Associated Nonferrous Metal Resources, Kunming 650031, China）
Abstract:The bending deformation method was adopted to characterize the creep deformation behavior of Al-Cu-Li alloy in the creep aging forming (CAF) process based on a series of CAF tests, and the evolution laws of its mechanical properties and microstructures under different pre-deformation conditions were studied. The results show that the bending creep strain characterization method can intuitively describe the creep variation. With the increase of the pre-deformation strain, the creep strain of the specimen firstly increases and then decreases. The increase of the pre-deformation strain can promote the course of aging precipitation, and improve the formed alloy’s tensile properties at room temperature, the Kahn tearing properties, and the fatigue propagation properties. Pre-rolled specimens produce a slightly weaker work hardening than pre-stretched specimens, but they also create a stronger aging-strengthening effect; thus the strength, toughness and damage performance can be improved to some extent. Among all the types of specimens, the specimen with 3% rolling after CAF treatment has the best comprehensive mechanical properties.
Key words: Al-Cu-Li alloy; creep aging forming; pre-deformation; bending creep strain; microstructure evolution; mechanical properties
