|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Ultrafine-grained Materials X
||Mechano-chemical Synthesis of Nb-oxide Cu Nanocomposites
||Qun Li, Xuekun Shang, Robert S Averback , Pascal Bellon
|On-Site Speaker (Planned)
Mechano-chemical processing is a versatile solid-state powder method for the synthesis of a large number of nano-composites. It is however often problematic to control the dispersion of immiscible refractory oxides in ductile matrices. Using Cu-Nb-O as a model system, we demonstrate that a two-step approach can successfully overcome this problem. In the first step, we take advantage of a self-organization reaction in the immiscible Cu-Nb system during ball milling at room temperature to control the density and size of Nb nanoprecipitates. In the second step, this nanocomposite is co-milled with CuO, resulting in the reduction of CuO and the oxidation of Nb nanoprecipitates. TEM characterization shows that three distinct types of Nb oxide precipitates are observed: homogenously dispersed nanocrystalline NbO (~3nm), Nb-Nb oxide core-shell inclusions (~20nm), and amorphous Nb-O rich agglomerates, which form during the later stage of milling. The extension to other systems is discussed.
||Planned: Supplemental Proceedings volume