Guangwen Xie

Annealing studies of TiN films deposited by plasma-assisted CVD

Abstract Titanium nitride films prepared by plasma-assisted chemical vapor deposition (PACVD) on high speed steel were heated in the range of 1073–1373 K. The samples were analyzed by microhardness, XRD, EDX, SEM and XPS. It was found that the annealing temperatures had significant effects on the composition, microstructure and mechanical properties of the films. The chlorine content and lattice parameters of the films were reduced with the rise of the annealing temperature. The microhardness of the films had a minimal value at the annealing temperature of 1173 K. These results were interpreted in terms of the changes of microstructures of the PACVD TiN films.

Preparation and characterization of polyethylene/TiO2 nanocomposites

The rheological behaviour, dispersion, crystallization behavior, mechanical properties, fracture surface morphology of polyethylene (PE)/TiO2 nanocomposites prepared by melt compounding were investigated using rheometer, energy dispersive X-ray spectrometer (EDX), polarized microscopy, impact tester, universal testing machine and field-emission scanning electron microscopy (FE-SEM). The rheological analysis indicated a fine dispersion of TiO2 during the melt compounding. The large scaled surface dispersion of TiO2 nanoparticles was revealed by the EDX composition distribution maps. The introduction of 2.0 wt% TiO2 in composites improved the mechanical properties significantly compared to neat PE, and resulted in 45% increase in notched impact strength. Moreover, the further analysis and discussion showed the mechanical properties of the composites were controlled by the dispersion conditions of TiO2 and its nucleating effect on PE crystallization.

Template‐Synthesized Copper Nanotubes via Electroless Plating

Template synthesis method of preparing copper nanotubes via electroless plating has been investigated in this paper. The tubular structures were obtained by calcinring copper‐coated carbon nanofibers. The final products were characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), and x‐ray diffractometer (XRD). The results show that copper nanotubes can be synthesized by this method. The inner diameter of the prepared copper nanotubes is about 100 nm, and the wall thickness is about 25 nm. In this method, it is convenient to control the dimension or the shape of the obtained copper nanotubes by using different nanofibers as templates.

Magnetic Properties of Ni‐Co‐B Coated Carbon Nanofibers

Continuous and uniform Ni‐Co‐B coatings were successfully deposited onto carbon nanofibers via electroless plating. SEM images of the prepared Ni‐Co‐B coated carbon nanofibers were presented. The magnetic properties of the coated carbon nanofibers were investigated. The CoSO4/(CoSO4+NiSO4) ratio in the electroless bath has obvious influence on the coercivity and residual magnetic flux density of the Ni‐Co‐B coated carbon nanofibers.