Sökning: "boron alloys"

Visar resultat 1 - 5 av 24 avhandlingar innehållade orden boron alloys.

1. 1. Disordered Icosahedral Boron-Rich Solids : A Theoretical Study of Thermodynamic Stability and Properties

   Författare :Annop Ektarawong; Björn Alling; Michael Widom; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Icosahedral boron-rich solids; Boron carbide; Configurational disorder; First-principles calculations; Thermodynamic stability; Superatom-special quasirandom structure;

   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

3. 2. Microstructure and mechanical properties of Ti-6Al-2Sn-4Zr-2Mo and Ti-6Al-4V : influence of H, O and B

   Författare :Raghuveer Gaddam; Barbara Shollock; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Titanium alloys; Hydrogen; Oxygen; Boron; Tensile; Compression; Fatigue; Metallography; Fractography; Materialteknik; Engineering Materials;

   Sammanfattning : Titanium and its alloys are used in a wide range of applications from aerospace, marine, biomedical implants and consumer goods, due to their superior specific strength, excellent corrosion resistance, and biocompatibility. In aerospace applications, these alloys are predominately used as components in the aero/rocket engines because of their high strength-to-density ratio compared to other metallic materials. LÄS MER

4. 3. Effect of boron and hydrogen on microstructure and mechanical properties of cast Ti-6Al-4V

   Författare :Raghuveer Gaddam; Magnus Hörnqvist; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Titanium alloy; Metallography; Fractography; Castings; Low cycle fatigue; Hydrogen; Boron; Materialteknik; Engineering Materials;

   Sammanfattning : Titanium and its alloys are widely used in applications ranging from aeroengines and offshore equipment to biomedical implants and sporting goods, owing to their high ratio of strength to density, excellent corrosion resistance, and biomedical compatibility. Among the titanium alloys used in aerospace, Ti-6Al-4V (an α+β alloy) is the most widely used, in applications in which the temperature may reach 350°C, at which point it retains good fatigue and fracture properties as well as moderate tensile strength and ductility. LÄS MER

5. 4. Weldability of Cast Superalloys - Effect of homogenization heat treatments on hot cracking susceptibility of cast Alloy 718, ATI® 718Plus®, and Haynes® 282®

   Författare :Sukhdeep Singh; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hot ductility; Segregation; Homogenization; Boron; Gleeble; Welding; Nickel-based superalloys; Varestraint; Hot cracking; Hot isostatic pressing; Niobium;

   Sammanfattning : Precipitation hardened Ni- and Ni–Fe-based superalloys are used in high-temperature sections of aero engines owing to their superior mechanical properties compared to those of the other alloys. However, their better mechanical performance is accompanied by its own challenges during the manufacturing process. LÄS MER

7. 5. Processing Methods for Reaching Full Density Powder Metallurgical Materials

   Författare :Maheswaran Vattur Sundaram; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gas atomised powder; water atomised powder; high density powder metallurgical materials; high density; master alloys; liquid phase sintering; sintering; high velocity compaction; hot isostatic pressing; additive manufacturing;

   Sammanfattning : Powder metallurgy (PM) is one of the most cost effective methods for manufacturing structural components with complex shapes. Utilisation of the metal powder to shape the components allows to minimise material waste and increase energy efficiency. LÄS MER