Sökning: "uniaxial flow"

Visar resultat 6 - 10 av 12 avhandlingar innehållade orden uniaxial flow.

  1. 6. Elastoplasticity of Grey Cast Iron FE-Algorithms and Biaxial Experiments

    Författare :Hans E. Hjelm; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Biaxial experiments; multiaxial elastoplastic behaviour; graphite flakes; FE-codes; hardening behaviour; graphitic grey cast iron;

    Sammanfattning : This thesis focuses on multiaxial elastoplastic behaviour of graphitic grey cast iron with the aim to provide physically appropriate and numerically reliable constitutive relations for use in FE-codes. To achieve this goal, this work is divided into three parts: Biaxial experiments are performed on thin cruciform specimens. LÄS MER

  3. 7. Improved high velocity cold copaction processing : polymer powder to high performance parts

    Författare :Bruska Azhdar; Sture Persson; Cornell Nicolescu; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; high-velocity compaction; powder polymers; polyamide-11; relaxation assist; compactibility; relative green density; morphology; pull-out; springback; Polymer chemistry; Polymerkemi;

    Sammanfattning : A uniaxial High-Velocity Compaction (HVC) process for polymer powder using a cylindrical, hardened steel die and a new technique with relaxation assist was tested with a focus on the compactibility characteristics and surface morphology of the compacted materials using various heights of relaxation assist device with different compacting profiles. Relaxation assist device was presented as a new technique to reduce springback, pull-out phenomenon and to improve the compaction process. LÄS MER

  4. 8. Mechanical behaviour of a roller bearing steel : Strength differential effect, low temperature creep and propagation of short cracks

    Författare :Irene Linares Arregui; Bo Alfredsson; Nils-Gunnar Ohlson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Fatigue cracks in bearings either initiate from the surface or from an inclusion below the rolling contact surface. Then, short cracks start to propagate. Short crack grow at considerably faster rates than long cracks subjected to a nominally equivalent stress intensity factor range. LÄS MER

  5. 9. Application of SiGe(C) in high performance MOSFETs and infrared detectors

    Författare :Mohammadreza Kolahdouz Esfahani; Henry Radamson; Ya-Hong Xie; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Silicon Germanium Carbon SiGeC ; Reduced Pressure Chemical Vapor Deposition RPCVD ; Epitaxy; Pattern Dependency; MOSFET; Mobility; bolometer; Quantum Well; Infrared IR Detection; Ni Silicide; High Resolution X-ray Diffraction HRXRD ; High Resolution Scanning Electron Microscopy HRSEM ; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

    Sammanfattning : Epitaxially grown SiGe(C) materials have a great importance for many device applications. In these applications, (strained or relaxed) SiGe(C) layers are grown either selectively on the active areas, or on the entire wafer. LÄS MER

  7. 10. Continuum modelling of the mechanical response of paper-based materials

    Författare :Eric Borgqvist; Hållfasthetslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; paperboard; constitutive modeling; anistropy; finte deformations; plasticity; damage; continuum mechanics;

    Sammanfattning : Continuum based elasto-plastic-damage models for paperboard have been established in this work. The thesis begins with an introductory section that describes the mechanical properties of paperboard and some of the converting processes during forming of a package. LÄS MER