中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 17 No. 4 August 2007 |
(1. School of Materials Science and Engineering, Nanchang University,
Nanchang 330047, China;
2. School of Mechanical and Electronic Engineering, Nanchang University,
Nanchang 330047, China)
Abstract:The semi-solid slurry of wrought aluminum alloy 2024 was prepared by a well developed rheocasting process, low superheat pouring with shearing field(LSPSF). The appreciate combination of pouring temperature and rotation speed of barrel, can give rise to a transition of the growth morphology of primary α(Al) from coarse-dendritic to coarse-particle-like and further to fine-globular. The combined effects of both localized rapid cooling and vigorous mixing during the initial stage of solidification can enhance wall nucleation and nuclei survival, which leads to the formation of fine-globular primary α(Al). By using semi-solid slurry prepared by LSPSF, direct squeeze cast cup-shaped component with improved mechanical properties such as yield strength of 198 MPa, ultimate tensile strength of 306 MPa and elongation of 10.4%, can be obtained.
Key words: semi-solid metal processing; wrought aluminum alloy; solidification; microstructure; mechanical property