Mechanical Properties and Thermal Stability of Nanostructured Al/Al_(12)(Fe,V)_3Si Alloys Produced by Powder Metallurgy

摘要

The present paper deals with the properties of bulk nanostructured Al-Fe-V-Si alloys containing 16, 27, and 37 vol.% of Al_(12)(Fe,V)_3Si precipitates. The elemental powders were subjected to high-energy ball milling for 60 h followed by hot-pressing in a uniaxial die at 550℃ under 300 MPa. Mechanical properties of consolidated samples were evaluated by hardness, room temperature, and high temperature compression tests and compared with those of rapid solidification-powder metallurgy (RS-PM) counterparts and also those available for conventional and high temperature Al alloys. The results showed that the nanostructured alloy containing Al_(12)(Fe,V)_3Si precipitates has good thermal stability at high temperatures. Room temperature compression tests demonstrated that the strength increases and the ductility decreases with increasing the volume percentage of Al_(12)(Fe,V)_3Si precipitates. The room temperature yield strength of nanostructured alloys was in the range of 560-758 MPa depending on Al_(12)(Fe,V)_3Si content. These values are much higher than those for RS-PM counterparts. In addition, nanostructured Al-Al_(12)(Fe,V)_3Si alloys exhibited better strength at elevated temperatures compared with other Al alloys.