Sökning: "transition metal alloys"
Visar resultat 1 - 5 av 70 avhandlingar innehållade orden transition metal alloys.
1. Transition Metal Nitrides : Alloy Design and Surface Transport Properties using Ab-initio and Classical Computational Methods
Sammanfattning : Enhanced toughness in brittle ceramic materials, such as transition metal nitrides (TMN), is achieved by optimizing the occupancy of shear-sensitive metallic electronic-states. This is the major result of my theoretical research, aimed to solve an inherent long-standing problem for hard ceramic protective coatings: brittleness. LÄS MER
2. Transition metal and alloy catalysts in the light of computational materials modelling
Sammanfattning : This thesis is built around two pillars. One is heterogeneous catalysis in the broader context of green chemistry. The focus here is on identifying catalytically active materials suitable for the valorization of renewable feedstocks. LÄS MER
3. Atomistic simulation and experimental studies of transition metal systems involving carbon and nitrogen
Sammanfattning : The present work was initiated to investigate the stability, structural and thermodynamic properties of transition metal carbides, nitrides and carbo-nitrides by atomistic simulations and experimentations. The interatomic pair potentials of Cr-Cr, Mn-Mn, Fe-Fe, C-C, Cr-C, Mn-C, Fe-C, Cr-Fe, Cr-N and Mn-N were inverted by the lattice inversion method and ab initio cohesive energies, and then employed to investigate the properties of Cr-, Mn- and Fe-carbides by atomistic simulations in this work. LÄS MER
4. Ab Initio Simulations of Transition Metal Alloys: Towards the Multiscale Modeling
Sammanfattning : The present thesis concerns applications of first principles electronic structure calculations in conjunction with methods of statistical mechanics for simulations of transition metal alloys both in the bulk and at surfaces.A fully relativistic generalization of the exact muffin-tin orbitals (EMTO) method has been developed. LÄS MER
5. Thermodynamic investigations of transition metal systems containing coabon and nitrogen
Sammanfattning : In view of the important applications of carbides and carbo-nitrides of transition metals in the heat-resistant and hard materials industries, the thermodynamic activities of Cr and Mn in the Cr-C, Fe-Cr-C, Mn-Ni-C and Mn-Ni-C-N systems have been studied in the present work by the use of the galvanic cell technique. CaF2single crystals were used as the solid electrolyte. LÄS MER