Sökning: "Dynamic strain ageing"

Visar resultat 1 - 5 av 13 avhandlingar innehållade orden Dynamic strain ageing.

1. 1. 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

3. 2. 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

4. 3. Improved Material Models for High Strength Steel

   Författare :Rikard Larsson; Larsgunnar Nilsson; Linköpings universitet; []
   Nyckelord :Plastic anisotropy; non-linear strain paths; mixed isotropic-kinematic hardening; isotropic-distortional hardening; dynamic strain ageing; static strain ageing; marten- sitic transformation;

   Sammanfattning : The mechanical behaviour of the three advanced high strength steel grades, Docol 600DP, Docol 1200M and HyTens 1000, has been experimentally investigated under various types of deformation, and material models have been developed, which account for the experimentally observed behaviour.Two extensive experimental programmes have been conducted in this work. LÄS MER

5. 4. Volumetric Analysis in Mechanical Behaviour and Physical Ageing of Polymers

   Författare :Mats Delin; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ageing rate; Gr neisen parameter; bulk modulus; KAHR model; dilatometry; Poisson s ratio; timescale; physical ageing; dynamic mechanical properties; stress relaxation; volume changes; creep; Doolittle s equation;

   Sammanfattning : Volumetric changes associated with the deformation of ideal elastic solids depends on elastic constants of the solid and applied strain. Their magnitude is easily determined from the corresponding Poisson's ratios. LÄS MER

7. 5. Influence of waxes on bitumen and asphalt concrete mixture performance

   Författare :Ylva Edwards; Ulf Isacsson; Klaus-Werner Damm; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bitumen; asphalt; additives; wax in bitumen; polyphosphoric acid in bitumen; rheology; IR-spectroscopy; dynamic mechanic analysis DMA ; bending beam rheometer BBR ; literature study; low temperature physical hardening; highway materials; morphology; modified bitumens; temperature susceptibility; low temperature performance; ageing; microscopy; chromatography; Fourier transform infrared spectroscopy; force ductility; conventional binder tests; asphalt performance; tensile strain restrained specimen test TSRST ; Building engineering; Byggnadsteknik;

   Sammanfattning : This doctoral thesis consists of a literature review, presented in two papers, and another six papers describing experimental studies of the influence of different kinds of wax and polyphosporic acid on bitumen and asphalt concrete mixture properties. The literature review should give an extensive description of the field of knowledge concerning wax in bitumen. LÄS MER