Search for dissertations about: "severe plastic deformation"

Showing result 1 - 5 of 25 swedish dissertations containing the words severe plastic deformation.

2. 1. The character of magnetic records of deformed soft sediments with emphasis on liquefaction structures

   Author : Guangyu Sun; Nils Axel Mörner; Don Tarling; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; magnetism; sediments; deformation; Earth sciences; Geovetenskap;

   Abstract : In this thesis the characteristics of magnetic records in deformed soft sediments during postglacial time in Sweden are studied. Magnetic records refer in this study to magnetic remanence (NRM and ChRM) and susceptibility, including its anisotropy (AMS). READ MORE

4. 2. Wear of high strength steels and ductile iron and its effect on fatigue performance

   Author : Abdulbaset Mussa; Pavel Krakhmalev; Jens Bergström; Bojan Podgornic; Karlstads universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sliding wear; severe plastic deformation; delamination; WEL and synergy of wear and fatigue; Materialteknik; Materials Engineering;

   Abstract : Machinery components used in demanding applications are required to transmit or carry mechanical loads under severe loading conditions. They are subjected to cyclic loading and repeated sliding contact that in many cases result in a premature failure of components. READ MORE

5. 3. Combined thermal and mechanical loading of railway wheel treads. A numerical study of material response and cracking under braking conditions

   Author : Sara Caprioli; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rolling Contact Fatigue; Ratchetting; Tread braking; Plastic deformation; Thermal cracking;

   Abstract : The scope of the thesis is prediction of the material response owing to combined thermal and mechanical loading of a railway wheel tread. The long-term objective is to improve models for prediction of surface-initiated Rolling Contact Fatigue (RCF) under the combined effect of mechanical loading due to rolling (and sliding) contact and thermal loading due to braking and/or wheel--rail friction. READ MORE

6. 4. Rail Corrugation Growth on Curves

   Author : Peter Torstensson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; short-pitch rail corrugation; rotating flexible wheelset model; small radius curves; prediction of long-term roughness growth; plastic deformation; non-Hertzian and non-steady wheel‒rail contact; wear; rutting corrugation;

   Abstract : The development of periodic irregularities with distinct wavelengths (corrugation) on the low rail of small radius curves is studied through mathematical modelling, numerical simulations, field measurements and laboratory investigations. One year of monitoring of roughness on the low rail of a 120 m radius curve on the metro of Stockholm Public Transport (SL) showed severe growth of rail corrugation with wavelengths of about 5 cm and 8 cm. READ MORE

7. 5. Microstructural changes in high strength steels exposed to large deformation and high strain rates

   Author : Kristina Ryttberg; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; deformation mechanisms; high-velocity forming; high-velocity parting-off; adiabatic shear band; cold ring rolling; TEM; steel;

   Abstract : Increasing steel prices and environmental aspects have put forward the demand to reduce material consumption and energy usage in manufacturing industry and near-net-shape manufacturing techniques have thus become increasingly important. High-velocity parting-off,high-velocity forming and cold ring rolling are three such manufacturing methods that exhibit great potentials in terms of material waste reduction. READ MORE