|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Bulk Processing of Nanostructured Powders and Nanopowders by Consolidation
||Precipitation Behavior of UFG Al6063-5vol%SiC Nanocomposites
||Xun Yao, Yifeng Zheng, Wei Zeng, Jiamiao Liang, Deliang Zhang
|On-Site Speaker (Planned)
An ultrafine grained Al6063-5vol%SiC nanocomposites (UFGNC) has been fabricated by high energy ball milling, spark plasma sintering (SPS) and hot extrusion. In order to compare the precipitation behavior of the UFGNC with that of the coarse grained (CG) material, Al6063 granules were directly consolidated by die pressing and hot extrusion to fabricate a CG Al6063 rods. The heat treatment involves solution treatment for 1 hour at 520℃, quenching and ageing for different times at 170℃. The hardness of UFGNC samples as a function of ageing timeshows no age-hardening tendency for the UFGNC, while the CG counterpart shows typical age hardening trend. Large quantities of G.P.Zones were observed in the microstructure of heat treated UFGNC sample without any needle shaped β’’ phase while the precipitates formed inside the grains of the CG alloy. It has been demonstrated that formation of G.P.Zones in UFGNC is easier than in the CG alloy, while the growth of them could be inhibited by the lack of Mg and Si solute atoms inside the grains, since they are attracted by particle/matrix interfaces and grain boundaries which work as solute atom sinks. Segregation of Si and Mg atoms to the grain boundaries and matrix/SiC interfaces has been observed.
||Planned: A print-only volume