Sökning: "visco-plastic material"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden visco-plastic material.

  1. 1. Micromechanical modeling of cleavage fracture in polycrystalline materials

    Detta är en avhandling från Stockholm : KTH

    Författare :Mateusz Stec; KTH.; [2008]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cleavage fracture; probabilistic modeling; brittle to ductile transition; cohesive zone; visco-plastic material; TECHNOLOGY Engineering mechanics; TEKNIKVETENSKAP Teknisk mekanik; TECHNOLOGY Other technology; TEKNIKVETENSKAP Övriga teknikvetenskaper;

    Sammanfattning : Cleavage fracture in ferritic steels can be defined as a sequence of few critical steps. At first nucleation of a microcrack takes place, often in a hard inclusion. This microcrack then propagates into the surrounding matrix material. The last obstacle before failure is the encounter of grain boundaries. LÄS MER

  2. 2. Computational modelling of machining - Mesh objective ductile damage modelling

    Detta är en avhandling från Stockholm : KTH

    Författare :SENAD RAZANICA; [2016]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ductile damage; fracture modeling; Mesh dependence; machining process; visco-plastic Johnson- Cook; simulation tool; FEM;

    Sammanfattning : AbstractTo strengthen the competitiveness the manufacturing industry strives for a continuousdevelopment of cost efficient manufacturing processes and improved product quality.These research and development issues are addressed by increasing the implementationof simulation tools based on finite element method (FEM). LÄS MER

  3. 3. On Peritectic Reactions and Transformations and Hot Forming of Cast Structures

    Detta är en avhandling från Stockholm : KTH

    Författare :Hani Nassar; KTH.; [2009]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; peritectic reactions; massive transformations; thermal analysis; Fe-base alloys; steels; growth irregularities; hot forming; compression testing; flow stress; grain size.; TECHNOLOGY Chemical engineering Metallurgical process and manufacturing engineering Metallurgical manufacturing engineering; TEKNIKVETENSKAP Kemiteknik Metallurgisk process- och produktionsteknik Metallurgisk produktionsteknik; TECHNOLOGY Chemical engineering Metallurgical process and manufacturing engineering Metallurgical process engineering; TEKNIKVETENSKAP Kemiteknik Metallurgisk process- och produktionsteknik Metallurgisk processteknik;

    Sammanfattning : This thesis deals with peritectic reactions and transformations that occur during the solidification of many alloys. Peritectics are believed to be a major cause of crack-formation in many steels, thus, good knowledge of the mechanisms by which these phenomena occur is essential for preventing such defects. LÄS MER

  4. 4. Ductile damage modeling of the machining process

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :SENAD RAZANICA; [2019]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ductile fracture; Damage threshold criterion; Damage evolution; Machining simulation; Mesh dependence; Thermodynamics; Johnson-Cook; Damage driving energy;

    Sammanfattning : Machining processes are among the most common manufacturing processes for producing components used on a daily basis. It is a complex material removal process. Today, the research and development within the manufacturing industry is addressed by cost efficient numerical simulation strategies rather than by costly experimental procedures. LÄS MER

  5. 5. Development of Energy-based Damage and Plasticity Models for Asphalt Concrete Mixtures

    Detta är en avhandling från KTH Royal Institute of Technology

    Författare :Ibrahim Onifade; KTH.; [2017]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; energy-based models; damage; X-ray computed tomography; continuum plasticity mechanics CPM; effective micro-crack stress; Transportvetenskap; Transport Science;

    Sammanfattning : Characterizing the full range of damage and plastic behaviour of asphalt mixtures under varying strain-rates and stress states is a complex and challenging task. One reason for this  is partly due to the strain rate and temperature dependent nature of the material as well as the variation in the properties of the constituent materials that make up the composite asphalt mixture. LÄS MER