Nano structured WC Co composite powders were prepared by high energy mechanical milling. The microstructure of as milled WC Co composite powders (including grain size, lattice strain, Co distribution and lattice ...Nano structured WC Co composite powders were prepared by high energy mechanical milling. The microstructure of as milled WC Co composite powders (including grain size, lattice strain, Co distribution and lattice defects) was investigated by X ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and energy dispersive X ray spectroscopy (EDS). Nano structured WC co vered and separated by cobalt thin layers with average grain size less than 10 nm was obtained by high energy mechanical milling. The morphology of WC grains is almost spherical. High energy mechanical milling could also bring about a large number of lattice defects in WC grains.展开更多
Spinel ferrite ZnFe 2O 4 powders were synthesized directly from ZnO and α Fe 2O 3 mixtures by high energy mechanical milling. X ray diffraction (XRD) and high resolution transmission electron microscopy (HRTE...Spinel ferrite ZnFe 2O 4 powders were synthesized directly from ZnO and α Fe 2O 3 mixtures by high energy mechanical milling. X ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) were used to investigate the chemical reaction processing at different milling time. It has been found that the solid reactions between metal oxides are characterized by stages. Once the solid chemical synthesized reaction is initialized, it proceeds quickly and can be completed in very short time. Grain sizes of ZnFe 2O 4 are less than 10 nm.展开更多
文摘Nano structured WC Co composite powders were prepared by high energy mechanical milling. The microstructure of as milled WC Co composite powders (including grain size, lattice strain, Co distribution and lattice defects) was investigated by X ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and energy dispersive X ray spectroscopy (EDS). Nano structured WC co vered and separated by cobalt thin layers with average grain size less than 10 nm was obtained by high energy mechanical milling. The morphology of WC grains is almost spherical. High energy mechanical milling could also bring about a large number of lattice defects in WC grains.
文摘Spinel ferrite ZnFe 2O 4 powders were synthesized directly from ZnO and α Fe 2O 3 mixtures by high energy mechanical milling. X ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) were used to investigate the chemical reaction processing at different milling time. It has been found that the solid reactions between metal oxides are characterized by stages. Once the solid chemical synthesized reaction is initialized, it proceeds quickly and can be completed in very short time. Grain sizes of ZnFe 2O 4 are less than 10 nm.
