Sökning: "DISLOCATIONS"

Visar resultat 16 - 20 av 141 avhandlingar innehållade ordet DISLOCATIONS.

  1. 16. As-cast AZ91D magnesium alloy properties : Effects of microstructure and temperature

    Författare :Hoda Dini; Anders E.W. Jarfors; Nils-Eric Andersson; Jönköping University; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magnesium; Magnesium Alloy; AZ91D; High-Pressure Die-Casting; Mechanical Property; Microstructural Characterisation; Physical Modelling; Dislocations; Distortion; Residual Stress; Magnesium; Magnesiumlegering; AZ91D; Pressgjutna; Mekanisk Egenskap; Mikrostrukturkarakterisering; Fysikalisk Modellering; Flytspänning; Dislokationer; Geometrisk Tolerans; Restspänning;

    Sammanfattning : Today, there is an essential need for lightweight, energy-efficient, environmentally benign engineering systems, and this is the driving force behind the development of a wide range of structural and functional materials for energy generation, energy storage, propulsion, and transportation. These challenges have motivated the use of magnesium alloys for lightweight structural systems. LÄS MER

  3. 17. Creep modelling of particle strengthened steels

    Författare :Hans Magnusson; Rolf Sandström; Göran Engberg; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Particle strengthening; dislocation climb; ferritic steels; dislocation evolution; creep rate modelling; Materials science; Teknisk materialvetenskap;

    Sammanfattning : Materials to be used in thermal power plants have to resist creep deformation for time periods up to 30 years. The role of alloying elements for creep strength of 9-12% Cr steels is analysed. The creep strength in these steels relies on minor additions of alloying elements. LÄS MER

  4. 18. Novel architectured, dislocation-free, III-Nitride structures for the next generation optoelectronic devices

    Författare :Maryam Khalilian; NanoLund: Centre for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; III-Nitride materials; heteroepitaxy; 3D growth mode; optoelectronic devices; Fysicumarkivet A:2019:Khalilian;

    Sammanfattning : III-Nitride (III-N) materials are promising building blocks of optoelectronic devices such as light emitting diode and laser diode due to the unique material properties. Furthermore, direct and tunable band gaps of III-N materials enable them to cover the entire visible-UV region of electromagnetic spectrum for device applications. LÄS MER

  5. 19. Calculations of defect related properties in semiconductors

    Författare :Sven Öberg; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Scientific Computing; Teknisk-vetenskapliga beräkningar;

    Sammanfattning : Many of the most important and useful properties of crystalline materials, such as mechanical strength and electrical resistance, are determined by the presence of lattice defects and impurities. Well known examples are dislocations which control plastic flow and make metals ductile, and dopant atoms which control the extrinsic conduction in semiconductors and insulators. LÄS MER

  7. 20. Orthopaedic Patients with Lower Limb Vascular Injuries

    Författare :Karin Bernhoff; Martin Björck; Sari Ponzer; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Orthopaedics; Ortopedi; Kirurgi; Surgery;

    Sammanfattning : Vascular injuries in lower limbs are rare but serious events. If not detected and managed correctly and timely they can lead to permanent functional impairment and even limb loss. The increasing number of orthopaedic interventions, worldwide, makes awareness of this problem among orthopaedic surgeons important. LÄS MER