Sökning: "Valeriu Chirita"

Hittade 5 avhandlingar innehållade orden Valeriu Chirita.

  1. 1. A theoretical study of mass transport processes on TiN(001) and mechanical properties of TiN- and VN-based ternaries

    Författare :Daniel Edström; Valeriu Chirita; Lars Hultman; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis concerns computer simulations, using classical molecular dynamics, of transport processes related to TiN(001) growth. It is motivated from the challenge to understand transport processes at the atomic scale responsible for crystal and film growth and their different growth modes. LÄS MER

  3. 2. Growth and Mechanical Properties of Transition Metal Nitrides and Carbides

    Författare :Daniel Edström; Valeriu Chirita; Lars Hultman; Denis Music; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The atomic-scale dynamical processes at play during film growth cannot be resolved by even the most advanced experimental methods. As such, computational methods, and chiefly classical molecular dynamics, are the only available research tools to study these processes. LÄS MER

  4. 3. Toughness enhancement in transition metal nitrides

    Författare :Davide Giuseppe Sangiovanni; Valeriu Chirita; Lars Hultman; Sergey Simak; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cubic; transition metal nitrides; mechanical properties; ab initio; dft; toughness; ductility; electronic structure; Condensed matter physics; Kondenserade materiens fysik;

    Sammanfattning : Toughness enhancements can be induced in cubic-B1 transition metal nitride alloys by an increased occupation of the d-t2g metallic states. In this Licentiate Thesis I use density functional theory to investigate the mechanical properties of TiN and VN and of the ternaries obtained by replacing 50% of Ti and V atoms with M (M = V, Nb, Ta, Mo, and W) to form ordered structures with minimum number of inter-metallic bonds. LÄS MER

  5. 4. Transition Metal Nitrides : Alloy Design and Surface Transport Properties using Ab-initio and Classical Computational Methods

    Författare :Davide G. Sangiovanni; Valeriu Chirita; Lars Hultman; Paul Mayrhofer; Linköpings universitet; []
    Nyckelord :;

    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

  7. 5. Development of molecular dynamics methodology for simulations of hard materials

    Författare :Peter Steneteg; Igor Abrikosov; Valeriu Chirita; Bruce Harmon; Linköpings universitet; []
    Nyckelord :;

    Sammanfattning : This thesis is focused on molecular dynamics simulations, both classical and ab initio. It is devoted to development of new methods and applications of molecular dynamics based techniques to a series of materials, all of which have the common property of being hard. LÄS MER