Sökning: "substitutional solid solutions"
Hittade 5 avhandlingar innehållade orden substitutional solid solutions.
1. Alloy Design for Refractory High Entropy Alloys with Better Balanced Mechanical Properties at Both Room Temperature and Elevated Temperatures
Sammanfattning : Motivated by the desire to improve the energy efficiency of gas turbines by operating them at higher temperatures (HT), which will contribute to a more energy efficient and carbonless society, the quest for novel ultrahigh-temperature materials can never be overwhelming. High entropy alloys, the recently emerged multi-component alloys with equiatomic or close-to-equiatomic compositions, are considered highly promising as next-generation ultrahigh-temperature materials. LÄS MER
2. Point defect interactions and structural stability of compounds
Sammanfattning : Theoretical studies of point defect interactions and structural stability of compounds have been performed using density functional theory. The defect-related properties, such as activation energy of diffusion, electronic and magnetic structure of selected materials have been studied. LÄS MER
3. First-principles study of configurational disorder in icosahedral boron-rich solids
Sammanfattning : This thesis is a theoretical study of configurationally disordered icosahedral boronrich solids, in particular boron carbides, using density functional theory and alloy theory. The goal is to resolve discrepancies, regarding the properties of boron carbides, between experiments and previous theoretical calculations which have been a controversial issue in the field of icosahedral boron-rich solids. LÄS MER
4. Disordered Icosahedral Boron-Rich Solids : A Theoretical Study of Thermodynamic Stability and Properties
Sammanfattning : This thesis is a theoretical study of configurational disorder in icosahedral boron-rich solids, in particular boron carbide, including also the development of a methodological framework for treating configurational disorder in such materials, namely superatom-special quasirandom structure (SA-SQS). In terms of its practical implementations, the SA-SQS method is demonstrated to be capable of efficiently modeling configurational disorder in icosahedral boron-rich solids, whiles the thermodynamic stability as well as the properties of the configurationally disordered icosahedral boron-rich solids, modeled from the SA-SQS method, can be directly investigated, using the density functional theory (DFT). LÄS MER
5. Theoretical description of Ti and Ti alloys from first principles
Sammanfattning : Modern world is known for many advanced technologies and solutions to complex problems. Technical progress runs at high speed. In order to most effectively use materials, given to us by Nature, it is important to know their properties. To do laboratory experiments is often too expensive and time consuming. LÄS MER
