|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Bulk Processing of Nanostructured Powders and Nanopowders by Consolidation
||Microstructures and Mechanical Properties of Ultrafine Grained Al-7Si-0.3Mg Alloy Produced by Thermomechanical Consolidation of a Milled Powder
||Jiamiao Liang, C. Kong, Md Zakaria Quadir, Yifeng Zheng, X. Yao, Paul R Munroe, Deliang Zhang
|On-Site Speaker (Planned)
A mechanically milled nanocrystalline Al-7Si-0.3Mg (wt%) alloy powder was consolidated by vacuum hot pressing (VHP) or spark plasma sintering (SPS) in combination with hot extrusion (HE). It was found that significant Si particle growth and GP zone precipitation occurred during the consolidation processes. Meanwhile, with increasing the amount of plastic deformation during extrusion the uniformity of Si particle distribution improves due to Si particle flow and redistribution. The nanograins of the alpha-Al matrix were quickly turned into ultrafine alpha Al grains during extrusion through plastic deformation induced dynamic recrystallization and rapid grain growth. The as-consolidated samples exhibited a yield strength of 298 and 269MPa, an ultimate tensile strength of 345 and 327MPa and an elongation to fracture of 5.9 and 7.8% for the VHP-HE and SPS-HE consolidation processes respectively. The microstructural reasons for the good mechanical properties of the consolidated samples are discussed.
||Planned: A print-only volume