Sökning: "Dynamic strain"

Visar resultat 1 - 5 av 187 avhandlingar innehållade orden Dynamic strain.

  1. 1. Monotonic and Cyclic Plastic Deformation of High-Strength Aluminium Alloys

    Författare :Magnus Hörnqvist Colliander; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strain rate effects; Heat treatment; Dynamic strain ageing; Precipitation hardening; Low cycle fatigue; AA7030; Plastic deformation; Temperature effects; EN AW-7030; Al-Zn-Mg; Strain hardening; Mechanical properties; Dynamic precipitation.;

    Sammanfattning : Dynamic strain ageing (DSA) and dynamic precipitation (DP) are two, closely interrelated, phenomena arising from the dynamic interaction between mobile solute atoms and dislocations. The occurrence of DSA and DP is confined to specific ranges of strain rate and temperature, and aluminium alloys are generally prone to experience DSA and DP already at ambient temperatures and conventional strainrates. LÄS MER

  3. 2. The Plastic Flow Behaviour of Aluminium Alloys Exhibiting Dynamic Strain Ageing

    Författare :Magnus Hörnqvist Colliander; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Al-Zn-Mg; Dynamic strain ageing; Strain rate sensitivity; Portevin-Le Chatelier effect; Temperature sensitivity; Thermal activation;

    Sammanfattning : The phenomenon known as dynamic strain ageing, abbreviated DSA, has been known since the beginning of last century. It was first discovered as serrations in the load-elongation curve obtained upon deforming specimens of certain alloys in tension. This phenomenon became known as the Portevin-Le Chatelier (PLC) effect. LÄS MER

  4. 3. Ultrastructural Aspects of Pulp Fibers as Studied by Dynamic FT-IR Spectroscopy

    Författare :Margaretha Åkerholm; KTH; []
    Nyckelord :cellulose; cooperation; crystallinity; dynamic test; glucomannan; hardwood; holocellulose; humidity; infrared spectroscopy; kraft pulp; lignin; mechanical pulp; orientation; polarised light; softwood; strain; sulphite pulp; viscoelasticity; xylan;

    Sammanfattning : Dynamic (or 2D) FT-IR spectroscopy in combination withpolarized IR irradiation has been used in this work to studywood polymer orientation and interactions on theultrastructural level in wood fibers in the native state aswell as the effects of different pulping processes. The woodpolymer interactions were studied under both dry and humidconditions. LÄS MER

  5. 4. Dynamic and meta-dynamic recrystallization of Ni-based superalloy Haynes 282

    Författare :Emil Eriksson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hot compression; EBSD; dynamic recrystallization; meta-dynamic recrystallization; Ni-base superalloys;

    Sammanfattning : Thermomechanical processes are a crucial manufacturing step because they can “reset” the microstructure, and set the starting point for all following steps. In turn, the microstructure can be used to tailor the mechanical properties of the material. LÄS MER

  7. 5. Finite Element Procedures in Modelling the Dynamic Properties of Rubber

    Författare :Anders K Olsson; Byggnadsmekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; akustik; vibration and acoustic engineering; Materiallära; materialteknik; Mechanical engineering; hydraulics; vacuum technology; Material technology; dynamic; amplitude; frequency; Technological sciences; Teknik; FEM; rubber; vibrationer; vakuumteknik; Maskinteknik; hydraulik;

    Sammanfattning : Rubber is not only a non-linear elastic material, it is also dependent on strain rate, temperature and strain amplitude. The non-linear elastic property and the strain amplitude dependence give a non-linear dynamic behavior that is covered by the models suggested in this thesis. LÄS MER