Kinetics of nanoscale structure development during Mg-vapour reduction of tantalum oxide
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R. Müller
Abstract
Electron microscopic observations revealed the development of a complex interpenetrating morphology of magnesia and tantalum after magnesium-vapour reduction of tantalum oxide powder. In the early reaction stage, a nanoscale lamellar and rod-like morphology is found. This rather regular structure decomposes and coarsens during further annealing. By leaching of magnesia, nanoporous tantalum with large inner surface area is obtained. A possible growth mechanism for the observed initial cellular structure is proposed. A theoretical analysis aims at finding the optimum process parameters in order to prepare and to stabilise especially fine magnesiatantalum structures as a base for producing highly nanoporous tantalum for capacitor applications.
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© 2007, Carl Hanser Verlag, München
Artikel in diesem Heft
- Contents
- Contents
- Editorial
- Professor Dr. phil. Dr. techn. e. h. Hellmut F. Fischmeister
- Basic
- Compressive deformation of lamellar microstructures – a short review
- Influence of external and internal length scale on the flow stress of copper
- Spinodal decomposition of cubic Ti1−xAlxN: Comparison between experiments and modeling
- Combined ab-initio and N-K, Ti-L2,3, V-L2,3 electron energy-loss near edge structure studies for TiN and VN films
- Gold-enhanced oxidation of silicon nanowires
- Numerical determination of parameterised failure curves for ductile structural materials
- Relaxation of semiconductor nanostructures using molecular dynamics with analytic bond order potentials*
- Examination of phase transformations in the system Fe–N–C by means of nitrocarburising reactions and secondary annealing experiments; the α + ∊ two-phase equilibrium
- Applied
- On the evolution of secondary hardening carbides in a high-speed steel characterised by APFIM and SANS
- Silicon nitride tools for hot rolling of high-alloyed steel and superalloy wires – load analysis and first practical tests
- Development of the unloading stiffness during cyclic plastic deformation of a high-strength aluminium alloy in different tempers
- Enhanced thermal stability of a cobalt–boron carbide nanocomposite by ion-implantation
- Experimental studies and thermodynamic simulation of phase transformations in high Nb containing γ-TiAl based alloys
- Kinetics of nanoscale structure development during Mg-vapour reduction of tantalum oxide
- On the interaction of ductile damage and materials softening of a Ni-base alloy during hot deformation
- Adhesive contact between flat punches with finite edge radius and an elastic half-space
- Notifications
- DGM News
Artikel in diesem Heft
- Contents
- Contents
- Editorial
- Professor Dr. phil. Dr. techn. e. h. Hellmut F. Fischmeister
- Basic
- Compressive deformation of lamellar microstructures – a short review
- Influence of external and internal length scale on the flow stress of copper
- Spinodal decomposition of cubic Ti1−xAlxN: Comparison between experiments and modeling
- Combined ab-initio and N-K, Ti-L2,3, V-L2,3 electron energy-loss near edge structure studies for TiN and VN films
- Gold-enhanced oxidation of silicon nanowires
- Numerical determination of parameterised failure curves for ductile structural materials
- Relaxation of semiconductor nanostructures using molecular dynamics with analytic bond order potentials*
- Examination of phase transformations in the system Fe–N–C by means of nitrocarburising reactions and secondary annealing experiments; the α + ∊ two-phase equilibrium
- Applied
- On the evolution of secondary hardening carbides in a high-speed steel characterised by APFIM and SANS
- Silicon nitride tools for hot rolling of high-alloyed steel and superalloy wires – load analysis and first practical tests
- Development of the unloading stiffness during cyclic plastic deformation of a high-strength aluminium alloy in different tempers
- Enhanced thermal stability of a cobalt–boron carbide nanocomposite by ion-implantation
- Experimental studies and thermodynamic simulation of phase transformations in high Nb containing γ-TiAl based alloys
- Kinetics of nanoscale structure development during Mg-vapour reduction of tantalum oxide
- On the interaction of ductile damage and materials softening of a Ni-base alloy during hot deformation
- Adhesive contact between flat punches with finite edge radius and an elastic half-space
- Notifications
- DGM News
