中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 20 No. 7 July 2010 |
mechanical properties of Mg-4Y-4Sm-0.5Zr alloy
（1. National Engineering Research Center for Nonferrous Metals Composites,
General Research Institute for Nonferrous Metals, Beijing 100088, China;
2. National Engineering Research Center of Light Alloys Net Forming,
State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering,
Shanghai Jiao Tong University, Shanghai 200240, China;
3. Université de Grenoble, Grenoble INP, Science et Ingénieriedes Matériaux et Procédés (SIMAP),
CNRS UMR 5266, UJF, BP 46, 38402 Saint-Martin d’Héres Cedex, France）
Abstract:The solution-treated Mg-4Y-4Sm-0.5Zr alloy was extruded at temperatures from 325 ˚C to 500 ˚C. Dynamic recrystallization (DRX) completely occurs when the alloy is extruded at 350℃ and above. The grains of the extruded alloy are obviously refined by the occurrence of DRX. The average grain size of the extruded alloy increases with increasing the extrusion temperature, leading to a slight decrease of the ultimate tensile strength (UTS) and the yield strength (YS). On the contrary, the UTS and YS of the extruded and aged alloy increase with increasing the extrusion temperature. Values of UTS of 400 MPa, YS larger than 300 MPa and elongation (EL) of 7% are achieved after extrusion at 400 ˚C and ageing at 200 ˚C for 16 h. Both grain refinement and precipitation are efficient strengthening mechanisms for the Mg-4Y-4Sm-0.5Zr alloy.
Key words: Mg-Y-Sm-Zr alloy; extrusion; heat treatment; ageing; mechanical properties
